I haven't programmed in a while, and have kind of lost interest, but I want to get back, and I've enjoyed C# the most, a lot more than objective-c and visual basic. So I want to make some games that me and my friends will be able to play next school year. So basically something you can play on the web.

What programming languages deploy to the web? If c# is possible, and a mac with safari/firefox would be able to use it (I can't install plugins, and I don't want to get in trouble for making myself admin again) Flash, Java, etc. If java does, I'd like that most since it's most like c#. Then what libraries/engines would I use? I want to do 2d. And then what IDE would I use?

Thanks in advance!