C:Drive Memory On CRITICAL / 'My Documents' Got Deleted

I have Windows 7 Home Premium, 32bit laptop. So this started with my accidentally deleting the 'My Documents'. At the time of deleting, i think it showed, My Documents is too large for recycle bin. That's why i can't find it there. (I have tried 'Recuva' to recover deleted files, but 'cause i'm not much of a computer literate, i didn't know what files to retrieve and what to leave. Though, from the files i did bring back, most are corrupted, overwritten or something.) Also, after My Documents got deleted, under 'C:Users', a padlock has appeared on my '(User Name) Folder' - but 'Public Folder' is fine. As i clicked 'User Name' properties, the 'Share With' showed - 'Nobody'. {other options available were 'Homegroup(read), Homegroup (readwrite) and Specific People'}. Shouldn't it be showing - 'Advance sharing' ?Thus, i thought maybe restoring 'User Name' folder to its previous version would work. When i did that, it said - not enough memory. i tried again, 'cause i knew there was more than half of its total capacity available. {I regularly keep a check on it.} But after repeating the restoring process, i again got 'Not Enough Memory'. Later, when i opened the C:Drive it really showed that suddenly the drive was low on space- very, very low. i tried 'disk clean' and deleted most of the things from there. Then i opened C:Drive to check. Instead of making more space, i saw 3.62 GB of Free Space lessen to 2.72 G.B ! However, i still tried for the forth time to restore 'User Name' folder to previous version and got the same regretable 'Not Enough Memory'.