I would try a search here.
I remember seeing posts about basically what you said. Unfortunately in your case, what others find useable may not be usable on your specific gamecube. Even though you don't want to adjust the gamecube laser, I beleive you or a buddy should find out what it is set at. The best method to get the cube open is with the pen trick. (The white circular pens with the black ends are perfect. )
Reason being, if you find that most mini-dvdr media is not working, you owuld have saved some time by getting a friend to lower the laser output. It isn't as dangerous as you may think. Having it set to 200 is not dangerous. The problem is, some GCs are actually set too HIGH. Example being the 400's. If your GC was set that high, it would probably have problems running legit gamecube games, let alone DVD-R media.