is there a difference between a video movie projector and a presentation projector?

1. set up in the home on a table or mouted to the ceiling style projector

2. a super light weight projector you take with you connect to your laptop and show business meeting slides and video

is there a difference
I am looking for a movie projector that I can connect to my laptop and play dvds on it and play them at home or should i get the style that stays in the house and is connected to my stereo and dvd player

what would
you recommend for system in which i could do both

which is cheeper

what brand/model would you suggest i can get with great displays for under a grand.

thanks

please only techs responces are requested i.e. circuit city ron and johns "all you do is install video all day" types

data projectors may have higher resolution specs in order to deal with greater visual info say from a laptop or pc and also brighter but it will may be too bright for home theater use.Bright in way that it may make the picture looked washed out or unatural and could also be hard on the eyes.Depending on how bright,it's like watching a really bright tv up close in the dark- that kind of strain.They are brighter because they are meant to be used in boardroom meetings with light in the room whereas home theaters are darker by nature..huh-lo 'home theater' -duh! The natural aspect ratio is also 4/3 squarish instead of 16.9 widescreen

Movie projectors have special dedicated processors and higher contrast to make it more natual looking and similar to film,which is easier on the eyes then a glairing bright projected image.I owned both before and the movie projector is by far a better image,though the data projecter was a little sharper in image being that it was1020x720 where as mine right now is 720x480 though I have it set on 1080x1020 compressed but it still looks WAY better then just standard 480p by far.If I were you get a dedicated 720p dlp with hdmi capabilites,it's worth it.480p even upconverted to 1080i is still a softer image then true 1080i let alone true 720p or 1080i/p. Though if you want something strictly for pc,i'd go for a high res data projector.
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