Control Panel -> Administrative Tools -> Services. Services manager will be shown here.

Download our easy access Administrative Services Tool here which will save you time and effort opening the control panel, shortcut to the desktop and one click is all you need to complete the tasks below, also if your computer is slow when booting up you might want to install RegCleaner here to find out what is running on startup.

From here you can activate or deactivate the services that run on your PC.
A lot are useless, but some of them are 100% necessary for the system to start.
By deactivating some of them, we can get better overall performance, more available resources and more free RAM.

So, getting back at it, here's a list with all Windows XP's services.
You can right-click and Proprieties on every service.

Complete list with Windows XP services that are running in background along with their description.

Don't use by default my recommanded setting; read all the explications first.

Alerter (DISABLE) - Announces users of administrative alerts. Usually useless.

Application Layer Gateway Service (Manual) - Used for Assign Publish and Remove software services. On manual, it will start only if needed.

Automatic Updates (DISABLE) - Useless. Goto windowsupadate.microsoft.com for any updates.

Backgroud Intelligent transfer Service (Manual) - Used for asincronous data transfer with http 1.1 servers.

ClipBook (DISABLE) - Used to stare information (cut/copy/paste) and share them with other PCs. Usually useless.

COM+ Event System (DISABLE) - There are almost no apps that use COM+, but on manual it will start if needed.

COM+ System Application (DISABLE) - Same as above.

Computer Browser (DISABLE) - A list with network computers. This service is not required for a stand-alone system. If you wanna share files, it must be started.

Cryptographic Services (DISABLE) - Confirms the signatures of the files in Windows. You could get certification warnings, but it does not affect system stability.

DHCP Client (DISABLE) - Gets a dynamic IP from your DHCP server. If you have a static IP(and IP that does not change) you can disable this service. If you use modems, let it activated. Warning: if you disable this service when having a dynamic IP your internet connection will stop working.

Distributed Link Tracking (DISABLE) - Maintains links with NTFS files in your PC or a domain. Usually not required.

Distributed Transaction Coordinator (DISABLE) - Takes care of the tranzactions that require multiple resources. Windows works withought this one too.

DNS Client (Automatic) - Takes care of DNS names and control functions of the Active Directory domain. Helps online. Live it on.

Error Reporting Service (DISABLE) - Calls home to Microsoft when errors occur. LOL; disable it.

Event log (Automatic) - This allows Event Log messages from the applications to be seen in Event Viewer. This should be on; windows can get very upsad if it's turned off.

Fast User Switching Compatibility (Automatic) - Disable it to get win2k logon window.

Fax Service (DISABLE) - Not installed by default, so leave it off.

FTP Publishing Service (DISABLE) - Used for having a FTP server or your network. Activate it only if you really need it.

Help and Suport (DISABLE) - Resource eater. Disable it. Warning: it will auto-activate if you access Start->Help or press F1.

Human Interface Device Access (DISABLE) - If any of your peripherals doesn't work, leave it on. If all's ok, disabled.

IIS Admin (DISABLE) - Usually used with a local web server of ftp.

IMAPI CD-Burning COM Service (DISABLE) - Used to "burn" CDs. Use Nero or A120% instead.

Indexing Service (DISABLE) - Super resource eater. Disable it.

Internet Connection Firewall and Internet Connection Sharing (MANUAL) - If you have shared internet access or shared files, let it on, else off.

ISPEC Services (DISABLE) - Enabled only for security-obsseded people.

Logical Disk Manager (DISABLE) - vital to run Disk Management MMC dynamic volume console. Useless otherwise.

Logical Disk Manager Administrative Service (DISABLE) - Same as above.

Message Queuing (DISABLE) - Not installed. Let it this way.

Message Queuing Triggers (DISABLE) - Same as above.

Messenger (DISABLE) - Send messages between clients and servers. I don't need it.

MS Software Shadow Copy Provider (DISABLE) - Used with Volume Shadow Copy Service.

Net Login (DISABLE) - Used to login to a Domain Controller.

NetMeeting Remote Desktop Sharing (DISABLE) - Security bug. Let it disabled.

Network Connections (Automatic) - Required for network setup. If internet works, disable it.

Network DDE (DISABLE) - Don't activate if you don't use the clipbook service.

Network DDE DSDM (DISABLE) - Same as above.

Network Location Awareness (NLA) (Manual) - Used with Internet Connection Sharing.

NT LM Security Suport Provider (DISABLE) - Not necesarry unless you use Message Queuing or a Telnet server.

Performance Logs and Alerts (DISABLE) - Gathers various performance info and logs it or activates an alert. Useless.

Plug and Play (Automatic) - If you change any components, this service will detect it (teoretically).

Portable Media Serial Number (DISABLE) - Gets serial numbers from connected mobile music players. Disable it if everything works fine.

Print Spooler (Automatic) - If you have a printer: auto, else disabled.

Protected Storage (DISABLE) - Allows saving local password or Autocomplete web information. Let it on if you use autocomplete.

QoS RSVP (DISABLE) - Get you some traffic control in a IPSEC network and for the apps that support QoS and also has an adapter that supports that.

Remote Access Auto Connection Manager (DISABLE/Manual) - Created a connection to a program when it requires an address. Disable it if sh*t happens. Live it manual for dial-up.

Remote Access Connection Manager (DISABLE/Manual) - Same as above.

Remote Desktop Help Session Manager (DISABLE) - Security breach. Stop it ASAP.

Remote Procedure Call (RPC) (Automatic) - Critical importance. Let it on automatic. Almost everything depends on this service.

Remote procedure Call (RPC) Locator (DISABLE) - data base evidence of RPC. Not interesting at all.

Remote Registry Service (DISABLE) - Security breach. Stop it ASAP. This allows other users to get access to your registry. LOL

Removable Storage (DISABLE) - Naturally this is not required but if you noticesomething wierd with your CD/DVD-R/RW let it on auto.

Routing and Remote Access (DISABLE) - You'll know if you need it. Let it disabled.

Secondary Logon (DISABLE) - Useless. Ancient remains of an obsolete service.

Security Accounts Manager (DISABLE) - Security breach. Turn it off.

Server (DISABLE) - If you have something shared, on, else off.

Shell Hardware Detection (DISABLE) - Autoplay for memory cards. You decide. (Disable if you don't have memory cards or donno if you do).

Smart Card (DISABLE) - If you don't have a "Smart Card", or donno what's one disable it.

Smart Card Helper (DISABLE) - Same as above.

SSDP Discovery Service (DISABLE) - Huge security risc (recognized by MS). Disable it.

System Event Notification (DISABLE) - Used with COM+;stuff like power events or logoffs/ons. Not required.

System Restore Service (DISABLE) - Mine's off. Your choice. Let it on if you have too much space to waste.

Task Scheduler (DISABLE) - Resource eater. Turn it off.

TCP/IP NetBIOS Helper Service (DISABLE) - If you don't use Netbios, disable it. It's also a security breach.

Telephony (DISABLE) - On only for Dial-up. Off else.

Telnet (DISABLE) - Security breach. Disable it.

Terminal Services (DISABLE) - Used for Fast User Switching, Remote Desktop & Remote Assistance. Daca you really use those, let it on, else off.

Themes (DISABLE) - Used for the stressful windows desktop things. Turn off.

Uninterruptible Power Supply (DISABLE) - If you don't have an Uninterruptible Power Supply, turn it off.

Universal Plug and Play Device Host (DISABLE) - Security breach but used with SSDP Discovery Service,detcts and configurs your UPnP devices in your network. Can be disabled.

Upload Manager (DISABLE) - Useless. Obsolete.

Volume Shadow Copy (DISABLE) - Unneeded. Only used by ms-backup.

Software Shadow Copy Provider Service. - Same as above.

Webclient (DISABLE) - Useless. Disable it.

Windows Audio (DISABLE) - Those nerve-crashing sounds. If you've changed them, or wanna suicide, leave it on. Else off.

Windows Image Acquisition (WIA) (Automatic) - Used for some Cameras/Videos. If SH with those, reenable it.

Windows Installer (Automatic) - Used for .mis installers. You could need it.

Windows Management Instrumentation (Automatic) - I think windows requires it. Auto. Procedure Call (RPC) needs this one on.

Windows Management Instrumentation Driver Extension (Automatic) - Same as above.

Windows Time (DISABLE) - Connects to a server to get correct time. Small security buggie. Disable it.

Wireless Zero Configuration (DISABLE) - Auto configuration for wireless devices. Turn off if you don't have wireless stuff.

WMI Performance Adapter (DISABLE) - don't see any use for it. Disable it.

Workstation (Automatic) - Must be auto. It's of major importance.