There are LCD projectors and DLP projectors
projectors are aimed at two types, office/classroom with high light output, usually computer native resolutions, and home theatre projectors with less output but better colors, and DVD or HD vdo resolutions and aspect ratios.
Panasonic, Sony, Epson were focusing on LCD projectors ( dont know about current )
Optoma, Viewsonic, hp, BenQ, mitsubishi on DLP projectors
for home theatre, depending on budget, i would recommend optoma HD20, epson 8350 or panasonic ptae4000