I have some DVDs that just aren't seen to be working in my mini mac. They're all from the same manufacturer, in a series. The first one worked. The second doesn't. The third and fourth ones do. I tried putting the second disc in my old Powerbook laptop, but it just froze. I had a heck of a time getting the dvd out. In my mini the system doesn't freeze. I've looked on the data on the second dvd and compared it to the ones I know work. The data looks the same! What could be going wrong? I paid alot of money for these DVDs... I would ask for my money back... but the company is no longer around. Any ideas?