iMac OS X 10.10.2 using Adobe CS3 problem

I'M READY TO PULL MY HAIR OUT!!! I've read as many things about reinstalling and none of it makes any sense....

I have the original disc's, I only want to reinstall Adobe Illustrator - I follow the directions to a point, then I'm told to put in the disc for Ai CS3 (OF WHICH THERE ARE 2...1 marked Application and 1 marked Content) but there is no indication which one they want ???? - tried both? no good! and I couldn't get just Ai CS3 - keeps saying there are "combining" files that go with it? but even when I said yes to that - it didn't do anything. DRAT... so 3 days later I'm still stuck... Please somebody HELP!!!!?????