Many of those games run at medium res (EGA), so you need a scaler that will handle that. arcademvs.com sells one. Theirs can also apparently output resolutions other than VGA/480p which might let you hit 1:1 pixels.
Doesn't solve your aspect ratio problem. You can barn-door it, but then you'll have rather large black bars on the side. If you stretch it, it will look wrong, but a surprisingly large number of people don't care (in fact, I've been yelled at for daring to even point it out).