You are basically asking if you go an buy a piece of junk, it can fix your lousy projector.
The answer is no.
http://www.projectorcentral.com/BenQ-PB6200.htm
Your projector is about half a decade out of production. It has no digital inputs and was designed for PowerPoint presentations.
If you want the most from that projector then you start with a HD signal from Blu-ray or cable/satellite.
But, if you want the most from projection you stop looking for cheap solutions to poor products and you just get a decent product.
Under $1000 will net you a fair number of home theater projectors with specifications which just kick the crud out of that old BenQ.
Nothing 1080p or anything, but I can promise you that the basic processing in that BenQ is far superior to what Faroudja was brining to the market a decade ago. You would be going from bad to worse, and instead you should be saving every cent you have for a projector which is actually designed for home theater instead of PowerPoint.