I like clisp, and I think it's a good, newbie-friendly, implementation.
But remember that thanks to the fact that CL has a standard definition,
one can write a CL program using any CL implementation, and deploy it
using another CL implementation. As long as one takes care of writing a
conforming program, ie. a program that doesn't take advantage of
implementation specific behavior.
Now, if she doesn't use emacs, perhaps I should advise ccl (clozure cl),
which comes with a nice editor (hemlock) on MacOSX.
--
__Pascal Bourguignon__
http://www.informatimago.com/
A bad day in () is better than a good day in {}.