Ok, if you can, go and delete ALL cookies from your computer. Empty your Internet temp folder too.
Delete all emails (if they reside on your harddrive) that have attachments with them.
Run your antivirus scan update to make sure you have the latest info then run a complete scan of your computer.
Go to this website and do another FREE virus scan. http://housecall.trendmicro.com/ I have found and it is suggested that having more than one virus scan done on your computer each month is a good thing to do. Don't forget to bookmark that site too! Sometimes not every antivirus company has every single virus listed so it's important to do 2 separate scans.

Ad-aware is a good product. You will find the free version from the company that makes it at http://www.lavasoft.com/
One note about Ad-aware...I have known it to mess with some peoples computers (not that it is viciously messed with, just that there may be something in their registry files that is not compatible with some folks computers). It is unlikely that it will happen to yours, but I just wanted to give you a heads up on it.

After you have done all this, if you have found viruses or trojans do what the scans tell you to do (if anything) to remove them. Some will automatically remove them, some will not, and you are still having issues with it, you can try a system restore to a point before all that started. I would suggest also running a defrag after all is said and done too because a lot of times, everything can get really fragmented and slow your computer's response time down.

If this doesn't help, let me know what's going on specifically and I'll do my best to help you through it! Good Luck!

Hugssss
J