Did you see the Video? So far I was Able to Run Metroid and Mario Bros on My Gopher using the Method above. Does it lag and Flash like crazy? Yes, but I am sure that it can be done. BTW I am willing to Reprogram Metroid (Nes) to work on the MD. I dont care How long it Takes. I just need the Instructions. OR willing to Perfect the Program above to Make it Work.
I'm going to assume this isn't a troll post, and that you're actually serious about this endeavor. Here's what you need to do: 1) Learn how to program for the Genesis pretty much inside and out. 2) Then learn how to program for the NES inside and inside, or at least have a very solid understanding of how it works. Only then, can you attempt to formulate a realistic approach to this problem. Yes, there is more than one approach. If you want playable speed, it's not going to be emulation unless you can somehow seriously overclock the 68k cpu emulation on this handheld device. So with that in mind, you need to look at replacing pieces of original game code with native 68k code. You'll need to do this as well for graphic and sound functions - be it real time or replacement, or something in between.
I doubt you'll do this, because unless it's solely for the sake of challenge - you could easily use a fraction of the amount of time it takes to do this, and just work/earn money to purchase a device that could emulate a lot more platforms on a handheld setup. But feel free to prove me wrong (I rather you would, to be honest. Because things like this are super cool).
You're also in the completely wrong kind of forum for this sort of thing, because this out completely out of the scope of 'romhacking'. You need to be asking these kind of questions at retro based development forums (such as spritesmind and nesdev).