You can try Phaser, this is a pure JavaScript engine, you have to write all the code.
There are Solar2d, Gideros Mobile and Love2d, all of them use Lua code to create the game and they can export to HTML5.
You also have libgdx and mini2Dx, both use Java to code the game.
There are some engines that use C# like Wave Engine, Red Flat Ball, Duality, etc, but I don't know a lot about them.
You can take a look at HaxeFlixel and even Heaps Engine, they use Haxe language and you can port to HTML5 too.
I hope this can help you. Let me know which one of these you like more.