For the Playstation 2 there was an SNK Classics and a couple Fatal Fury collections that I downloaded. Holy crap do these games look like... CRAP. The same high school programmers that wrote your Atari collection wrote all three of these games I obtained. These are the douchebags that have never heard of "perspective". The pixels are actually, well, I don't know what you call that shape but it ain't a square. The games run fine and whatnot but they totally ruined the visuals so I can't play 'em.
I'm currently to the point to where I'm wondering if I could get a small form factor PC, use an HDMI or DVI cable to connect it to my television and get it to display properly there so I can just play my favorite arcade games there since no one knows how to properly port video output on a damn console.