System restore will only affect installed programs. It will not bring back personal documents deleted.
When you delete something from your hard drive, it is not deleted. The space is just marked as empty so as it can be overwritten.
There are "undelete" programs out there, but by installing one you run the risk of overwriting the data you deleted.
Best thing to do IMHO, remove the drive and attach it to another pc. Run Easy Recovery Professional, and that will get your info back.
Oh, DO NOT DEFRAGMENT your hard disc. This will rearrange the data on your hard disc, and your info will be gone forever.
Best of luck !