Hello memoman and welcome to Seven Forums.
I'm not quite sure what you mean by "system repair". There's System Restore that can (hopefully) restore your computer to an earlier date/time before the problem began. System Restore
There's Startup Repair that may fix certain problems, such as a missing or damaged MBR boot file that might prevent Windows from starting correctly. Startup Repair
Then there are diagnostic/repair scans that can sometimes fix startup issues. SFC /SCANNOW Command - System File Checker Troubleshoot Application Conflicts by Performing a Clean Startup
And then there's something called a Repair Install where you try to rebuild the entire Windows 7 operating system without affecting your user accounts, personal data, programs, system drivers, etc. Repair Install
Did you try using one or more of these tools and if so, which one(s)?