I remember from testing other cars, using a DVM to test is O.K. if you are able (with a friend) to test under load. When testing, no load, 12.5v +/- .5 is O.K. Have someone test under the load of starting. It should not drop below 11.25v. If it does, the battery is in sad shape, you can try charging it, but chances are that unless you have had it drained fairly well recently, it is toast.