Computer effected by some type of virus (i think)

Hi there,
I am new to the forum and after looking through some of the topics, it sesms that u guys can really solve problems! Anyways, i have a problem on my xp. Yesterday, i was surfing the web and i encountered a problem. My McAfee anti-virus picked this up, but i accidently pressed allow instead of block. Now some type of adware is on my comp. I went to search files/ folders in xp and searched for files created during the time the prob occoured. Many of the files were modified and some were created. i deleted most of the created ones, but cant get to delete two of the created ones because windows says it is being used by another program. I tried deleting every process in task manager and then tried deleting this, but it still says it is being used by another program. Anyways, my problem now is that in task manager, iexplore.exe always keeps opening up and whenever i am actually using internet explorer, random pop-ups come up. (Note: iexplore.exe keeps taking up a lot more ram then usual, and when ever i try to end this task, it just kees coming back up). I would appreciate any help with this problem.

PS: Im sorry but i dnont know what an HJT log is so if some1 can tell me wat it is, i wil be glad to post it
Thank you