Games not running in full screen/not playing in full resolution

[tmt345]

EDIT: I just realized this, GC games aren't widescreen so they shouldn't be widescreen is this correct?

The gamecube games I have tried (like MK Double Dash) will go into fullscreen mode but I have bars on the side and the quality looks like its possibly just being stretched and that its not really 1600x900.

I think this may be correlated with it... I noticed that while I was looking at this guide:
http://www.dolphin-emu.org/performance.html

I don't have the "Emulator Display Settings" under the General tab. I am, however, able to choose the display settings under the graphics settings but I'm not sure if this could mean its not working properly.

thanks for any and all help,
tmt345