|Mostly no for the first part, definitely no for the second. Most games will make changes to the registry when they are installed that are vital to their functionality. Simply sharing their files over the network won't make them playable.|
Even if the game could be shared successfully over a network, the game isn't going to magically start working on computers it couldn't run on before. If they are too slow to "download" or install on, they are too slow to play the game.