How old is the DVD drive.
The most common failure item in a computer built in the past 10 years is the optical drive. The laser burns out, or the laser gets out of alignment, or the belt slips, or the drive wheel slips.
They generally last about a year, but if you use them a lot, they will fail after six months.
Luckily, they are very inexpensive nowadays. You can replace one from Wal-Mart, or Best Buy, or Target, or Circuit City, or the remaining CompUSA for about $$24 to $29 to $34 to $39. Four screws, and some cable exchanges, and you are done... if you can figger out how to get into the case.
