Note: Click on any image for a larger view of that particular image.
Click 
then 
Type msconfig then click 
Click on the Startup tab, then uncheck programs you don’t want starting (by starting, I mean that these programs are always running, so by disabling them they won’t auto start but don’t worry, these programs will still be accessible).
In XP Essential programs are loaded through something called 'Windows Services.' This means that most of the startup items you see in XP are completely optional and can be turned off.
As a good rule of thumb if you don’t recognize the program name leave it on. If you see one that is blank (see below example) DEFINITELY DISABLE IT. These are usually spyware or viruses and you definitely don’t want them starting with your computer. When I see these I always run a Virus Check, then scan for Spyware.
Reboot your computer and you should notice faster performance.