Electrical (ground) problem

My car just developed an electrical problem. I got in the car, which was warm (driven five minutes ago), and turned the key and two of the lights came on (I forget which two), and nothing else happened. The radio did not turn on, nothing. When I turned the key to the start mode, the lights that did come on did not dim. I pulled a voltmeter and checked voltage at the cigarette lighter, and it did not read anything. Then I searched the fuse box for a faulty fuse and could not find any. Then I went under the hood to see if I could find anything, and I did not see anything offhand. The battery cables seemed clean and pretty tight. I was looking for another fuse box (I know some cars have this) but could not find any. I then started shaking things around and I heard a noise (click or something) from near the battery area (I was on the driver side so I am not sure exactly where it was). Then I went back into the car and saw the radio's clock was on, and reset. I tried turning the key to start the car and it started right up. :) Then I went back to the hood to double check things, and the only thing I noticed (after touching and shaking things) was that the ground wire that connects the battery to the body of the car was getting very hot. I checked the voltage between the and of the battery and the body of the car seemed to be about.8 volts (does not seem like much, but I would think it should less, like maybe one?). It is a cheap Radio Shack meter with bad leads on it, so that may be part of my diagnosis problem too. The heavy gauge and cable that connects the battery to the engine is in place and not hot. Does not the engine and add to the body and too or is the only and between battery and body that thin (10 gauge I think it looked like) wire? Is the problem a bad connection there or can there be another problem? Thanks in advance for all your help! -- AshayinFLA