Task Manager in XP

I seem to have a huge amount of processes on my task manager; many more than I ever remember being there before. How do I disable these from running unless I specifically call for the program? They seem to come back over and over no matter how many times I delete them. How do I actually find out what begins to run at start up and then being able to chose for it not to run every time I reboot? Probably a stupid and obvious question but it is escaping me.... :confused

 

Just to add to TimW's suggestion...if you have CCleaner, it has a start up manager as well. :clap

 

i thought i've seen somewhere here in the forums, that ccleaner's startup manager isn't as effective as others..something about that it only reads startup items in some places, but not all...but im not too sure.

 

I've already used Ccleaner but I'll download one of the other programs recommended. Thanks.