My DC is dead because of CD-R's pt. 2

Like I told in my other post, my DC is dead. It DOES NOT go to the screen with the "FILE, etc" screen. It really tries to boot the game, but somehow when the game ####ts to load, it randomly resets itself. Now, I can try to adjust the laser, but I can also get a new one if I give it to the store where I bought it... So what should I do??? And more important, how can I prevent that my DC goes dead so fast next time??? PLEASE tell me!!!!!