My name is Kelvin and recently I have discovered an editing program for the classic SNES game Ken Griffey Jr. Presents: Major League Baseball.  I played this game a lot as a kid and due to a lack of employment following completion of graduate school, I've recently had a lot of time on my hands.  Being a complete baseball nerd, I've so far completed two new versions of Ken Griffey Jr. Presents: Major League Baseball for Super Nintendo which you can download and play on your computer through use of an emulator.
 

If you are new to video game emulation, it's a way to play console video games on your computer.  "Emulators" take the place of gaming systems and you play "ROMs," which are the substitute for the game cartridge.  In order to play the ROMs I've created, you will need to download a SNES emulator.  I use zSNES on my PC, which I have been told is a little outdated, but it has worked for me.  You can do your own research.  If you are using a MAC, one emulator you can use is SNES9x. I would also recommend getting some sort of USB controller (PS3 controllers can be used), otherwise it's going to be very hard for you.