strange stuff going on with my comp

Everytime i log into windows, Zone Alarm picks up a new program witha random name (usually like oel3992.exe or something with lettersand number in that type of order). I've run AVG update a few times and then scanned my system, and i haven't found any viruses.

Has this happened to anyone before? What could this be?

I tracked down the programs a week ago and deleted the folder they were in, but next time i logged on, the folder was back and the problem persisted.

(and, on an unrelated note, wtf is Xupite(o?)r?)

Xupiter is a very annoying hard to rid yourself of spyware that is a search toolbar. It takes a good 15 steps to rid yourself of it, and I've heard there's newer versions of the thing too. If you have it then it'll be rough to rid yourself of.
For this and the problems you stated in the beginning, look up a program called Spybot search and destroy. It works great, i used it to rid myself of a bunch of spyware programs (particularly that damned comet cursor my mom downloaded). It's free and has a continually updating list of spyware and viruses. Run it and it should find your problems. It also finds registry inconsistencies and allows you to delete crap that takes up space like recently used streams in windows explorer...crap you don't need/want. Good luck.