Hi,
Sounds like the motor on it is going or the disc keeps getting stuck inside.
Either way get a new DVD drive.
To retrieve your CD, look on the front of the drive and you will see a small hole, straighten a paperclip and keeping it very level push it into the hole, when it meets resistance push it firmly but evenly, minding not to stick the other end of the clip into your hand. The drive will open enough to get your fingertips in to open it the rest of the way.