Assuming you are indeed backing up your entire startup drive, then yes, you can restore your computer to a usable state from a Time Machine backup.
If you're worried about documents and such, just take a look inside /Backups.backupdb on your Time Machine drive. Everything should be there.[/QUOTE
thank you for the quick response. i have a question tho, do i have to manually copy everything from my time machine backup back on, or is there a way to automatically do this?