I just put a DVD drive into my Indigo Clamshell, I have not overclocked it, but playing DVD's does not work (well)

in OS X. I used a version of VLC appropriate to OS 10.3.9.

This might be because the encoding is done in software and 366mhz just ain't enough hertz.

However, I can report that upon booting into OS 9.2.2 that the Apple DVD player plays them full screen

and without issue

I guess this must be because Apple DVD player software utilises directly the Rage Mobility chip.

+ having 576mb of RAM, probably helped