I've had my MacBook 4,1 since fall '08 and last year my optical drive started not reading DVDs or CDs. The computer just spits out any disc after what I assume is trying to load for like 20 seconds. Does this sound like a bad optical drive or something else? I'd hate to waste money getting a repair at the apple store, so is this something I can manage myself, at home? What brand optical drive, and from where, would you recommend? Thanks for the help!