hello there,
your post confused me a little. why do you want to do system restore and go back to when you hadn't used combofix? what has gone wrong? as for deleting DSW.Delf.2.AQ infection, you need a good anti-spyware, you hadn't mentioned if you got one. AVG is antivirus and it's not for removing infections like DSW.Delf.2.AQ. if you hadn't tried running antispyware yet, i recommend running
malwarebyte's antimalware :
http://www.2-spyware.com/review-malwarebytes-anti-malware.html i use it myself and it's pretty good with removing computer parasites.