Well, you don't need to exactly download an emulator. Theres a site, that he made to be able to play old classic games without having to download everything.
He has converted many emulators, but one big one was, "ZSnes". So you just need the plugin, and theres a whole butt-load of games of Click-And-Play.
http://www.vizzedboard.com/retro/(Guest accounts have only 5 plays per day. You must create an account for unlimited access.)
(Note that this site is not illegal. It's like you pay virtual money to play.)