you could download some emulators and roms like n64 and super smash bros but it helps if you have atleast 1 controller and the other person use keyboard or 2 controllers even better or get snes emualator and get secret of mana 2 its coop and you have 9 characters to chose from i think and alot more but these games are old so dont expect and good graphics haha have a good day
try ASTER (www.ibik.ru ) : "ASTER: Multiseat Software for MS Windows XP/ 7/ 8/ 8.1
ASTER is a program (and only a program!), which allows a lot of users to work with one computer independently as if each of them had their own PC."