Please give the exact wording of the error message and the exact details of your computer.
might be a silly question but.... disks scratched?
I was going to ask something similar to Jayson's question.
The error messages that you're seeing are generic Mac OS error messages for when any application is damaged. My first thought is that the installation file is in some way corrupted.
Try installing onto a different computer. If you've tried installing from the same media (discs or downloaded files) on multiple computers, and the installation isn't working, then you may want to try replacement media.
There's a link for contacting Adobe Support in the upper-right of this page. Customer Service should be able to help you if you need to order replacement media because of a damaged disc.