Greetings!

Somewhat challenging with a large party. Two is okay, but the keyboard is really too small for it. If you have something like this, though, it really helps.

As for ROM images, the official way is to obtain a set of physical ROMs for the games you like and read them in yourself. The "grey area" where I lurk is that I own physical copies of the ROMs I use, but use ROMs someone else encoded. Of course, people bootleg ROMs, just like MP3 files.

I have never hunted for ROMs on the net, so I don't really have any good sites to recommend. You might use the MAME site as a starting point.