computer bogged down

I have a 950mhz with 750megs of ram and I am having problems with it being extremely slow on bootup and loading pages. I’ve scanned my computer for viruses and none were found (both with my norton and online). Aside from reinstalling a fresh os is there anything I missed?

btw, anyonw know what amch.questionmarket.com (http://209.67.27.16/)is? I am seeing that on the bottom of my screen when logged in to yahoo email while uploading an attachmentand and I have to use the refresh button to get back to my email. I can ping the site but site is down?

Thanks