I am a teacher, and I need to get a projector for my classroom. I alternate between a Windows 7 and an older MAC, so it has to work with both. I also need to move it around a lot - often carrying it to different locations - so portability is pretty important. Also, the rooms are rarely darker than "dimly lit", and I have numerous high definition nature videos I want to show the kids. I just need to be able to project a large screen-sized image - probably nothing more than 8' x 8' (a little smaller would be OK).
Obviously I can't afford a ton of money, but more importantly is getting the right specs. I've looked at various reviews, and the different specifications leave me baffled. Can you recommend a projector, or at least a reliable resource for helping me make the right choice?