I'm ok when it comes to working on PC's and basic stuff, when it gets more advanced I'm lost.
In recent projects I often get stuck at the advance configuration level.
So situations where I need to remap joysticks, etc, often pose big problems for me.
Ideal situation would be multiple emulators that all match the iPac (MAME) default key codes, however PS1 emulation I know doesn't, neither does NullDC, and I believe the same is true of Project 64. (not that they don't match, but certain keys used by the iPac can't be used)
I like sticking with what I know (as limited as that may be). Like Brian74 I was actually thinking of using different emulators for the same console, namely for Sega as I like Fusion but it has no light gun support.
With Fusion I can exit with ESC, I get it to load full screen, and I believe I easily mapped my keys. I'm thinking that I should use another Sega emulator for Gun Games. I can simply copy of the gun games to one folder and for that emulator simply point it to that folder, this way only the gun games come up.
Lastly I found this tutorial for installing Aim Traks into original GunCon's. Like the idea of using some additional joystick cherry switches (real arcade switches) that I have on hand.
http://jaswin.net/mame/installing-aimtrak-into-a-guncon-case/