Hi, It's normal to have a lot of stuff visible in Task Manager in WinXP (and Win2000). I think 20-30 items isn't unusual. You can use the msconfig app to prevent nonessential things loading at startup, and also change some unused services from auto to manual (in Control Panel->Administrative Tools) which might improve things a little. Make a note of what u remove or disable in case it stops something important from working.
I'm running WinXP with 256MB, and there are definitely times when that's not enough and the system starts thrashing the disk cache... particularly when loading a new map in online games of RTCW