Antivirus software autoloaded-now cannot run laptop!

I was on my laptop yesterday. Suddenly a popup from "Security Tool" (supposedly Windows) appeared saying my computer was infected with over 100 trojans, etc. It had already auto-downloaded and scanned the computer; in order to remove all the stuff I would have to pay almost $50.00. However, I was repeatedly being told that several of the trojans were attempting to transmit my credit card info over the internet!

Regardless of what I've done, I cannot remove this "Program". It is also blocking the installation of any other trojan/malware programs.

I even disconnected from the inet, and it still works the same as before. How can I get rid of this annoying and troublesome thing?

Thanks in Advance,

Surfinwahine

Info:
Gateway Laptop Model MT3708
Win XP Home Premium
Genuine Dual Core Intel Premium
T2080 @ 1.73GHz 1.73 GHz
958 MB RAM
32-bit OS
ATI Radeon Xpress 200M Graphics
DVD +/- RW Drive and 4 in 1 Media Reader

 

You need to go to the Malware FOrum & follow the READ & RUN Sticky in there. Be sure to read thru it all first & then post the requested logs in there afterwards.

 

Agreed - I just finished a machine with the exact same symptoms, and the Malware Forum's procedures worked well...