I recommend Lua. http://www.lua.org/

Small, free, real simple, and beginner-friendly. And the language also supports advanced programming techniques that you can move onto later.

Ignore the Perl suggestion, Perl is a horrible beginner language, full of special cases and confusing semantics and other stuff. Basically, Perl will make you hate programming.

Python or Ruby.

I personally prefer Ruby over Python, since is has a cleaner syntax and fewer strange quirks, but both are equally powerful. They have nice learning curves too.

I would not recommend perl, for the same reasons >>43 mentioned. I learned perl after several other languages, and I still remember beating my head over it.

C and Java are right out. Especially Java. Any compiled language should not be used as a first language. Any language that makes you jump hoops to do anything especially so. Java is criminal here.

I disagree with Javascript, because alone it doesn't let you do much interesting except websites. The plus side is most browsers come with an interpreter.