We've talked about the issue of old home-burnt CDs and DVDs no longer being readable before on this site, but I did something this week that you may want to emulate: if you have CDs or DVDs, especially ones that contain a fully produced end product (like a DVD with menus), use ImgBurn to rip ISO files of the discs. An ISO is basically just an image of the disc - a big file that, if burned back to a DVD or CD using the proper program, gives you an exact duplicate of the disc. ImgBurn is a free program (but do donate if you use it and like it - I did) that makes the task of both ripping and burning disc images wonderfully simple.
Over the past ten years or so, I've created a handful of wedding DVDs for friends, and last week I thought "You know, if I'm the keeper of the master copy, I should make sure these never fade away" and I ripped them all to ISO files. It's a good thing I did that, because the oldest of the DVDs (about eight years old) gave me a few read errors on one computer - which likely means it's starting to degrade. It's kind of mind-blowing how fragile home-burnt CDs and DVDs can be - you should trust nothing to them, always having a solid backup of the information on them (hopefully on a hard drive).