Malware detected, clean now but comp still running poorly.

Is this the Dell Factory Install? It is often too much to ask for a Repair Install to sort out all the corruption that a grossly inferior Factory Install wreaks on the OS. Much better to invest in a perfect Clean Reinstall Windows 7
which will give the opportunity to experience native Win7 performance for the first time on that PC. You only need to do it once and then save the finished product as a backup image to use in place of reinstall.

Ok so to give an update. I tried once again to do a repair install and it worked the 2nd time. I believe I had forgotten to disable my Microsoft Security Essentials before I tried it the 1st time. The comp is now back to where it was before the virus. It appears to be clean now. Thank you to everyone that posted and helped out! I will go ahead and mark this as solved.