In most places it is legal to make copies of software for personal use so long as only one copy is run at one time. I am not a lawyer and this isn't legal advice, but I believe this is true in the United States, Canada, and Europe so long as the CD doesn't have any copy protection.
Therefore, for personal use, in such places you can legally make a binary image file of the disc (an "ISO") and then use virtual drive software to load the image so that it appears to be a CD drive with the disc in it. I've done this personally with my very played copy of Oblivion since I started to get concerned about disc damage.
I won't recommend any particular software because it depends so much on your exact OS and sometimes on you disc drive, but any CD cloner and any virtual CD drive software will do the job.