It depends on what you'd like to achieve. Looking at the settings there aren't all that many options. Reference/Cinema should be the right preset to start with, I'm not sure how Sharpness operates on the Optoma. I would guess 1 would be right, but play around with it to check the effect - if you crank it all the way up you should see that it creates outlines around contrasted edges. Text or channel logos are a good way to spot it, back it down until the outlines disappear completely - if that's close to 1 then 1 is probably the right setting, otherwise leave it where it is (sometimes the setting is closer to the middle and going beyond that actively softens the picture).
AVS HD ( http://www.avsforum.com/forum/139-display-calibration/948496-avs-hd-709-blu-ray-mp4-calibration.html
) contains patterns that can help you figure it out. There are also patterns there that will help you set the correct Brightness and Contrast level. Noise Reduction should be left at 0 if you're feeding the projector from a quality source. Gamma I'd imagine Film is probably the right setting, Colour Space: Auto if you have an HTPC in the mix, RGB (16-235) if it's just BD/DVD and broadcast TV. Don't know what effect that BrilliantColor has, I'd guess 1 would be right, but test it on various material and see what effect it has. I would also leave Dynamic Black Off.
"Colour Settings" are only adjustable with a meter and software.
These are just best guesses based on what I'm seeing here in the manual. I'll read a few reviews when I get back from the gym and come back to you if I find anything of note.