2 blinks means the drive has problems reading the disc. If it happens with all media, alll the time, the drive is bad. If it happens with a specific disc, ir is intermittant with that disc, send it back to the vendor for replacement--the disc is bad and can't be read.
The sequence should be: insert the disc. The light should go amber for 10-20 seconds (CD about 10 seconds, DVD about 15-20 seconds), then go green. It should stay green until you do something like read or write. If you get a single blink or series of blinks, it is a drive diagnostic code. It it happens with all media, the drive is bad.