cannot boot from CD

[Harry Kuhman]

I cannot boot from a CD that I burnt knoppix on to it just says somthing like cant read drive.

Amazing that you can't even give us the actual error message instead of a "something like ...:. I was going to speculate that you made some of the common burning errors, but even then you don't usually get "cant read drive" (or even "can't read drive"). See answer #1.