Ok, this is what I'm hoping to do. I want it to look like a completely white room, like in the Apple commercials, and i want to be standing there, and have me talking to another me. Get it? I know I'd have to film what I'm saying for each "me" twice, but I don't get how to get them on the same screen or get everything else to be white. Sorry if this is too confusing. I'll try it like this. Take the apple commercials, but take one guy out, let's say the PC guy, then "clone" the mac guy, and have him talking to his clone. Better? I don't know if I'd do this in after effects or Vegas, so I posted here.

setup set, don't move camera.

shoot one side then other...change costumes and positions between.

put one track over the other in your editor and set the composite mode on the top to screen. with a white background, it should just knock out the white background of the top and show the rest...although it may washout the top footage a bit.

Perhaps, you could use a chroma key to knock out whie and make sure that you aren't wearing any white...although bits of your eyes may disappear (so per haps green/blue screen would do a better job.

Can I use Vegas for this? If so, just drag one above the other, and how do I set the composite?

Why not shoot it over a white BG, first one side, then shoot the other.

Put the two layers in your editor one on top of the other and crop the top layer by half. Slide around to sync up.

Check out http://ryanw.michaelfrisk.com/ryan-w/index.html for some tutorials on doing just that.

yeah, just chroma key it out. That'll be the easiest way. Just make sure you get the timing right for the speaking.

Not chroma key.
This would normally be shot on a white background.
You can get HUGE rolls of white paper (12 feet wide, 50 feet long) for around $30 for this exact purpose at most pro photo supply stores.

Shoot the two "characters" seperately on the white background.
Apply a levels or curves filter to the captured video to make the whites "really white".
To finish, set up a timeline with a white color background.
Add the first character and reposition to one side of the frame.
Add the second character, positioned to the other side of the frame, and apply a mask (if needed) to make sure the first character is not covered by any white background from the top layer.

This should work in most video editing programs or VFX apps.
Any questions?

Or you can try a luma key... that would work with a white background, as long as you plan your costume appropriately.

http://rileyharmon.com/wordpress/?page_id=13 :-)

Nice one Riley!
Really like the camera work.

The blend on the merry-go-round split screen shot was particularly cool (though I think it shows just a little towards the very end).

Have fun.