In regard to getting up and running in Windows, the smoothest FOSS alternative is Lispcabinet. It allows multiple Lisps to be installed (e.g. it will install Clisp, closure, and sbcl), it integrates all of them with SLIME, and installs GNUemacs along with many useful utilities. It is about as painfree as anything which requires learning Emacs can be.<p>LispIDE is another Windows option. It is very minimal but doesn't require dealing with emacs.<p><a href="http://lispcabinet.sourceforge.net/" rel="nofollow">http://lispcabinet.sourceforge.net/</a><p><a href="http://www.daansystems.com/lispide/" rel="nofollow">http://www.daansystems.com/lispide/</a>