Sara,
Here is your post and its answers:
http://www.avsforum.com/avs-vb/showt...08#post1590208
It's good to keep reading the forum for information as you continue to look at buying a front projector. Another site, that answers questions about throw distances is projectorcentral.com. There is a projection calculator on the home page. Find the projector, type in one aspect, and the rest is calculated for you. Very useful. You can also find the specs of most projectors there. Also very useful. Be sure to see a DLP projector, an LCD, and an LCD with MLA, before you settle on any particular model. If you can swing seeing an LCOS or CRT, that will help, also. Once you have the performance of a particular projector in a particular technology in your experience, it makes the decision much easier. Then, seeing your first few choices in person helps, too. I didn't have that luxury, but I did see the LCD with MLA, and I was sold... My husband recently saw an LCD without MLA and he is very pleased we have the projector we have. Rainbows can be a problem with some DLP's, but what I noticed more, is that the background seemed to "move" in a flashy way. Not everyone sees this. There were some other artifacts that annoyed me, temporal dithering in particular, and so I wasn't happy at all with that demo. When the LCD projector was displayed, I was thrilled (Sanyo XP21N, btw) with what I saw. Good luck!