computer troubles

[EsPo]

ok, im installing UT 2k3, and i insert the disc (disc 1), then go to windows explorer, and i get please insert disc into D:. the disc clearly has been inserted and i can hear the drive reading the disc.. yet it doesnt detect the disc. ive tried run then d: but get the same message.. any ideas?

[EsPo]

im thinking its my computer.. cause i put a music cd in and that didnt work either.