I've had this 360 sitting in my closet for close to 2 years and finally decided to play with it. 90% of the time when I pop a game in it tries to read it then goes back to Open Tray. Every once in a while it'll come up as Unplayable Disc, and once it went to a black screen and the laser kept shuffling around for a good 5 minutes before I shut it off. So far I've tried cleaning and lubing the spindle and the pot tweak, no results on either. There doesn't appear to be any problem with the motor as far as I can tell, though when I put a game in there is some clicking. Not sure where that's coming from or if it's related. Is there anything else I should try? Most things I read seem to only apply to flashed drives and problems with backups. Drive is a Samsung TS-H943 M28, if that's at all relevant.

Looks like your DVd drive is about dead. Obtain the key from your current DVD drive and buy a replacement one on ebay. Then spoof the DVD key from your old drive to your replacement one. There are plently of guides knocking about on how to do this.