I think Lua is a particularly good language to learn early: it's quite small and very approachable for somebody vaguely familiar with the C languages, but it has coroutines, tall-call optimization, and quite a bit of flexibility via its meta-tables. I haven't used it on anything big enough to know if it's really practical for me as a getting-stuff-done language, but it's really growing on me.
Also, can of worms and all, but the borders between "an OO language" and "a scripting language" are quite thin. You could learn OO from Python or (I suspect) Ruby. OO design made quite a bit more sense to me when it didn't have to work around flaws in C, C++, and Java's type systems.
My favorite thing about Lua is the way you can fit all of the syntax in your head. I never have to go to a reference
when writing everyday code in Lua.
Also, can of worms and all, but the borders between "an OO language" and "a scripting language" are quite thin. You could learn OO from Python or (I suspect) Ruby. OO design made quite a bit more sense to me when it didn't have to work around flaws in C, C++, and Java's type systems.