www.consoleclassix.com
BTW you MUST be connected to the internet while using this emu if your not you will be disconnected from your game and yes you can save your games and it will store the saved game files for you so you can play them as if you were sitting at the ol Super nintendo itself.
NES/Atari are free SNES/GAMEBOY/GENESIS you would have to pay 5 bucks a month for this is a LEGAL<--- emulator and you can read the info for yourself on the site its a big blue tab that says Legal Info. Its basically an online blockbuster to sum it up of old games. How is this related to single player RPGS.... don't even ask SNES/NES have many including the original Final Fantasy for NES if your an FF nerd or are curious enough definately play that one... and Final Fantasy is a free one
Some other good plays
Secret of Mana-SNES(I HIGHLY recommend this one its made by squaresoft)
Legend of Zelda a link to the past- SNES(very good play highly recommended)
Barts Nightmare-SNES/Genesis (Kinda challanging imo but the courses in it are fun what you do is step on the pieces of paper to enter a course you'll see what I mean if you play the game)
Jurassic Park - Genesis( you can be a raptor or grant good times)
Golden Axe 2-Genesis(Good fun,very short and sweet)
All the mario games
Super Mario RPG-SNES(you turn based guys will eat this up)
Super Kirby All stars-SNES
Kirby's Dream Course-SNES
Prince of Persia-SNES(can be quite fun as well give it a try)
These are just a small crumb of the total amount of games on this thing it would take you awhile to beat every game on this console classix thing:P they have a very extensive list.