Hi cherrybee,
You should really start windows in "safe mode" to try to make sure the trojan isn't active when you scan with your antivirus etc. stuff. You start in safe mode by pressing F8 at the appropriate point during the bootup of your computer (this can be a little tricky to time but there should be a brief text message during bootup if you're quick enough to spot it).
When in safe mode try all your scans with system restore disabled.
If you're able to use the internet, you could try downloading
AVG Anti-Spyware 7.5 which seems to be quite effective.