Mostly: No.
1. RP compares the file attributes of SOME Apple-only system files against lists stored in "BOM" files in /Library/Receipts and attempts to restore them to those values. It does nothing for third-party apps, user files, external disks.....
2. RP frequently (if not always) reports "errors" which aren't actually errors.
It's often cited as the first thing to try for any problem, when in fact you might just as well wave chicken bones over your Mac.
If you have a problem:
1. Look at the crash report. It might look like mumbo-jumbo, but it may give you some clue. If it mentions third-party add-ons, or consistently references USB libraries, then that's worth a poke.
2. Try a new user account. This is a TEST, not a solution. If everything works in the new account, you know that something in your old account is the cause -- a preference, cache file might be corrupted, or something that loads like a Login Item might be conflicting somehow. Go back to your old account and try to eliminate the cause.
If the problem still exists in the new account, then the issue is system-wide. (Again, most probably an installed third-party add-on or low-level software that runs constantly in the background.)
Most third-party apps that promise to "clean" your Mac, or run regular "maintenance" are bogus or dangerous. I would recommend Onyx, which is a nice GUI front-end to lots of built-in utilities which you might need/want to try to fix a problem. Again, none of them need to be run regularly. (Beware: with great power comes the ability to makes things worse.)
