Unexplainable Mac Issues

Everything seems to be running okay right now, but I had to erase and install many times. At first it started with freezing after I let the computer sleep overnight. Then I had to force restart it. It was like this on and off for a week, so I backed everything up to an external drive using time machine. Then it got worse, I started having grey screens and after a battle of trying to get the OSX CD to work I was finally able to erase-install osx again. I started fresh, I even ran Disk Warrior to keep things clean. Eventually things got worse again, Disk Warrior then got stuck with overlapped files, I gave up after an hour, I read that issue could last days and weeks but I didn't have to recover anything. I had to erase and install again. This time carefully placing files back on one at a time. I kept rebuilding the disk on DW because of all the errors and checking Disk Utility for errors, but the Hard Drive seems to be perfectly fine all of a sudden. I only have a few things on my computer now, it froze 3 times on me so far but I was able to get it running again through DW and rebuild, etc.

Any programs out there that could possibly clean the disks from all the mess? I think the Hard Drive is OK but it is kind of messed up with all of the force shut downs and the rebuilding... Any suggestions would help, because this could only get worse again....