Disk drive reading osx cds but won't read windows 7 bootcamp cd

[soldierA21]

Hey all. Just like it says I'm having issues trying to reinstall windows 7 bootcamp on my mac. I've researched as much as possible online but I haven't really found anyone with the same issues resolved. I have a late 2009 model mac pro 2.8Ghz and I've had it over a couple years. I had windows 7 installed once on bootcamp a while back and not too long ago I erased and tried to reinstall it and its not recognizing those same cds I used before. Everything else seems to work fine. DVDs play and I can even run my mac osx cds. Is there something I need to change in settings, etc? I know it can't be the optical drive since everything else is reading just fine and my windows cds are not scratched and look fine to me, even play just fine on another computer with windows installed. I'm not sure what else to do to get them to work. Any advice?? Thanks.