You need to dig around and do some reading like the rest of us have.
"best set-up for viewing, video-wise" means the best way to set up where you physically play to see the screen well. Is that what you mean? The answer to that would be on a TV screen.
Again, reading will answer a lot of this that has taken some of us several hours to play with and test. If you don't have an XBOX, you have the 360 and PS2 (or the PS2 emulator). The best system for downloading rosters is also a question of personal opinion. For some having to mess with the save file on the PS2 emulator is annoying and for others having to figure out how to put files on an XBOX or 360 is annoying. Read and figure out what is involved in each and then learn how to do them and then decide which version you prefer.
Are the PS2 emulator graphics tweaks worth trying out? Again, you'll have to try. For me, no they're not. I play the game on an original XBOX and will continue to but that's just what makes me happy. Focus on what you CAN run first, then worry about which way you're going to play.