[Native and maximum resolution is 1680x1050. That is the resolution you will want to run games in to get the best picture quality as long as the game supports it.
DVD movies are 480p, so 640x480 resolution. DVDs look very good on it with my 6800GT and Nvidia Purevideo. And like was said, most all DVDs are wide-screen now, however most actually are not 16:9, and FYI, the aspect of this monitor is 16x10 (as are most wide-screen computer monitors. Most movies are actually wider and slimmer than 16x9, but they vary. This means you will still have some top and bottom bars, as is the case with wide-screen TVs as well. It is just way better than 4:3 aspect ratio.
As far as the Mac question, not sure, but TBH I don't see how it wouldn't work
BTW, games I have that support the resolution:
All HL2 games (CS:S, DOD:S, HL2 etc.)
Games I have that do not support it:
BF2 (don't play it anyways
However, FEAR works with directions found here
. You will also find many games on that site that can be fixed to work with your resolution.