Business Projector Versus A Home Theater Projector? Is There That Much Of A Difference In Black Levels?

I am budgeting about 500-600 for the project and about 100 for the screen. I can afford a 2000 projector.
A ViewSonic PJ506D SVGA (800×600) 4:3/16:9 2000 lumens business projector is going for 500 with a mail free screen and mount offer.
An InFocus In72 WVGA (852×480) 900 lumens home theater projector is going for about the same refurbished with no extras.
I have read that I really should get a home theater projector rather than a business projector like the 506D, but the lumens scares me.
I am projecting on an 80″screen with blinds and curtains closed. no lights. still some ambient light.
Which will be better. I am going to use it the a really nice DVD player, Wii and Home theater PC. No interest in HD DVDs for atleast 3-4 years when I will prob upgrade this anyway.