Today. Success. I finally loaded Mountain Lion and it’s running successfully on my mid-2009 MacbookPro. I loaded it onto my secondary drive instead of my primary drive. In the process, the problems I’ve been having with Mail got repaired, so it’s also running smoothly. There’s must be some issue with my primary disk drive, but I’ve run Tech Tool Pro, Disk Tools Pro, and Disk Utility on it and can’t find a problem.
We’ll I don’t care. It’s all working now. Now I just have to figure out how to use all the new features of Mountain Lion.