There is another way..... maybe. It depends if you've got the System Restore option turned on.
Go to:
Start / Programs / accessories / system tools / system restore
If you have the option turned on, the Restore My Computer to an Earlier Time will be selected.
Click NEXT, then you will get a calendar with available dates in a blue font. Pick a date in the past that you think may not have been infected by the trojan and follow instructions (a next or continue)
Your pc will start the restore process.
Note, anything you had installed after that date will have to be reinstalled.
This isn't like a format, it only works on the operating system, not your data files, pictures, mp3's docs, etc. They will be saft.
If the restore doesn't work, try another date.
Best of luck, and hope it works! I've saved many friends a lot of hassle with this. Generally restore is turned on by default, but many shut it off to save time in power on and shutdowns.
All it takes is for it to save your "life" one time and you'll always keep it turned on.