copy of passport for visa

Visa for what? Might be best to confirm it with the French embassy/consulate in Washington.

A regular color copy will work. I assume your are applying for a student visa or some other type of visa to stay more than 90 days.

A photo copy machine is fine. Make multiple copies, and make sure everything is included in them, nothing is cut off etc.

I don't envy you applying for a French Visa, I did it last year, and it was trying. Make sure you have copies of everything, and keep some for yourself incase. They can be very picky, the other girl who applied for one from my school was denied the first time, so make sure you send it in early enough to give you time to resend it if necessary

Just FYI not everyone who reads and posts here is a US/Canadian/Aus/NZ/EU citizen. I am, but there are indeed other folks here who do need a visa to enter most European countries. For example, my wife is a US Green Card holder, but she still travels on her foreign passport, so she needs a visa to enter Europe (and getting visas for her every time we vacation overseas is something of a PITA).

For many non-US citizens visiting France, you need to apply for a Schengen visa (good for most, but not all, of the European community).

It's not clear to me if the original poster is actually applying for a visa, or just asking what they should carry along with them. If it's just a question of what to carry along, just make a couple of photocopies of the main/front page of your passport, and the page that has the Schengen visa. Normal photocopies are fine.

If they're asking about what they need to actually apply for the visa, then they should carefully follow the directions from the French consulate (the application is more or less the same for any Schengen country, although there can be a few minor details about how they process it that differ). In any case it pays to get it right -- any country (not just France) is picky about visa details there days (so is the USA).