My Computer is slow

[NLSoldier]

I have a dell laptop with a 3.2 ghz pentium 4 proccessor and 512 MB of ram. Yet it runs incredibly slow. For example it does things like take a long time to open programs, and when I type the words on the screen lag behind the speed I actually tyep them at, and when I scroll down pages fast it lags a ton too. It also takes a while for my mouse clicks to register, especially on the poker action buttons. I have 2 dell 2001pfs hooked up to it, im not sure if that affects anything or not. Basically, it lags a ton when I try to do more than one thing at once, such as browsse 2+2 while playing poker. And it cant really handle more than 4 tables of poker. In a different post, someone reccomended making a perm swapfile...I have no idea what that is. Ive also been told to make sure nothing is running in the backround. Is there a way to see/change which programs run when the computer starts up? I run virus scans and ad-aware fairly frequently, so I dont think its virus/adware problem, but its still possible. Any ideas?

Thanks.