Best Emulators for Making Maps/Ripping Backgrounds

[LooneyTunerIan]

In your best opinions, what are the best emulators for ripping maps?

For examples:

NES
SNES
Game Boy Color/Advance
Sega Genesis
Arcade

[GHS]

For arcades mame of course (f4, time map viewer) but some game you would have to use older versions.
For genesise/MD Gens Re-Rrcording (has option for pink background to separate layers from the black transparant BG), wish other emulators had that.