No no no! You don't need to back anything up and start over.
Are you familiar with msconfig? Here's where you disable as much ugly stuff as possible. Click Start>Run then type msconfig then click OK. You DO have to be careful though not to disable important stuff. Look at the paths of the files and you'll know what it belongs to. If it looks funny, it probably is. If you aren't comfortable at all....skip this.
You'll need to reboot afterwards. If it boots back up, Right-click on My Computer and choose properties. Go to the System Restore tab and put a check where it says to Disable System Restore.
Go here and download (red link):
ATF-Cleaner.exe - www.atribune.org
Select all after you run it and let it clean your temp files
Then go to:
Malwarebytes Anti-Malware - Free software downloads and software reviews - CNET Download.com
Let it update and then do a quick scan. Then proceed
Then go here with Internet Explorer:
Free Online Scanner - Online Virus Scanner | F-Secure
or
Free Online Virus Scan | BitDefender Online Scanner (any browser)
or
HouseCall - Free Online Virus Scan - Trend Micro USA