I had a similar problem a few months ago but the damage was less severe. Your computer is probably filled with spyware and IE hijackers. Here is one suggestion:
Use a safety/start-up disk to start Windows. Go to the Web and get AdAware, Spybot, and the new MicroSoft anti-spyware beta (from their site). Run these programs and clean your computer.
Next, install a firewall. A firewall will slow yr. computer slightly (depending on your base processor speed and RAM) but the protection is great.
Get the latest anti-virus definitions and run an updated virus check.
Finally, install either Firefox or Opera and use either as a browser in the future. HTH.
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