First, you need fMSX-DOS (a very good MSX emulator), the system .ROM-files and the Metal Gear 2 .ROM-file. Unzip the files to a directory and type at the command line :

FMSX-DOS -ROM 2 SOLIDE12.ROM -MSX2 -VIDEO 2

Some text will appear. Just press any key to continue. Then the MSX-logo will come up and finally the Metal Gear 2 titlescreen. Have fun with this great game. If you're still having trouble to get it to work, e-mail me.