please look, as much help needed as possable

dunno whats going on, guess i got a virus or something.

when to log into my ebay last night and it came up, some box about security alert

something about the sites certificate has expired or not yet valid

this has happend when i tried to log on to ebay, fiestaturbo.com, paypal i cant get in to msn, and if i try and get my hotmail emails it comes up also,

anyone shed some light on whats going on?

ive scanned my pc witht the ad aware and removed 5 critical objects and loads of not so critical stuff, but even when i start up now im gettimg problems

anyone help me out