Windows 7 is no different at all.
All Windows past XP don't have the self-repair ability as the predecessors do.
All versions of VISTA except the Ultimate Version (where it has data recovery, etc. etc.) and all versions of Windows 7 except for the Ultimate version do not have the ability to do the type of self-repair you're wanting to do.
Best bet, start from scratch. If you have any ability to do so, transfer files/programs to an External Hard Drive or something, erase your drive, and start from scratch.
And welcome to the Windows Operating Systems.
All data is removed, is what overwritten means. you're better of clearing your drive. Or you'll have conflict errors. (Blue Screen of Death) the moment old programming starts interacting with the new.
One of the serious faults of all versions of VISTA, and 7, is if you don't wipe the drive clean before installing a fresh copy, is that the old programming has a bad tendency to "bleed through" the data in a later date.
