Thanks. I was actually more attracted to scheme, then did become a bit confused, but maybe I should just head over to lisp and check harder to see what's what.
Scheme is good, easy to learn and flexible; don't get me wrong: i just wanted to remark that it isn't very portable.
It isn't difficult to jump from Scheme to Lisp and viceversa; they are similar in many aspects.
If you want a quick comparison between Common Lisp and Scheme it would go like this: Common Lisp is a standarized, extremely powerful and flexible programming language; while Scheme is a do-it-yourself kit for creating your own extremely powerful and flexible programming language.
You are lumping them together, as you mention, but they are very different precisely on this regard: Scheme has a lot of very different implementations but code portability is an issue, while Lisp (Common Lisp) has a dozen implementations but code written in CL will generally compile and run straight away in any of them, due to language standarization.
Another lisp-like language to consider is Clojure, in its JVM implementation.