My philosophy is to almost never disable services. I believe in having a very consistently configured machine with the least number of tweaks possible. That gets me, IMHO, a stable machine and no surprises at Windows Update. (I guess that means I'll never use vLite! :))
The well known tweaking guides out there are not written from a sysadmin's viewpoint.
However, you can go to Add/Remove Programs and go to Windows Features, and turn off those you don't use. I never ever use, for example, Simple TCP/IP Services, on anything. There are no doubt other examples. If you find you need the feature you can turn it back on.
Same goes for server roles; if you have SNMP installed but don't use it because you don't have a device that uses it (or the tools to use it costs too much/are bloated/make no sense) then remove it.
But I never go and disable a service just to try and make things "faster".
Related: http://superuser.com/questions/923/what-can-i-turn-off-on-windows-xp-to-free-up-memory-without-breaking-everything
– Lance Roberts – 2011-08-24T01:51:51.003Not an answer, just a quick tip. Use http://www.null-logics.com/software/windows-service-commander/ to easily - start/stop/edit services - install/uninstall services
– Mercer Traieste – 2009-07-15T07:38:23.730None! They're lightweight and there for a reason (most of them). – alex – 2010-01-18T11:27:51.133
1@alex: bzzzt wrong! thank you for playing! – quack quixote – 2010-01-18T12:44:28.447
@~quack name a few that really affect performance. – alex – 2010-01-18T13:26:27.210
1@alex: what, Indexing Service & System Restore aren't obvious performance hogs? try running without them for a while. (assuming you can live without SR.) Portable Media Serial Number service? lighweight, sure, but there for a reason? On a fresh XP SP3 install that's never seen a portable media player? – quack quixote – 2010-01-18T19:47:44.433
I'll take my System Restore, thank you very much. I've needed it once, but it saved my behind that one time to make it worth its time. – alex – 2010-01-18T20:25:20.027