Get Firefox. Stop looking at kinky tentacle rape porn. BOOT INTO SAFE MODE.
Do this:
Start Menu > Run > msconfig
See what programs are starting up. Kill them all.
Check autoexec.bat for the same thing.
Run a full virus scan with multiple programs.
Remember that every time you look at kinky tentacle rape porn, god kills a kitten.
Try NOD32, AVG, and Spybot Search and Destroy. Or at least, those are your good free options.
If that doesn't work, just reformat.
Oh, and stay away from suspicious things.
Like kinky tentacle rape porn.
\o/