There are plenty of alternative scripting languages that work on Windows, UNIX, Linux, as well as other OSs.
Perl would probably be the best choice. Perl is a high-level, general-purpose, interpreted, dynamic programming language. Perl can do just about anything OS related that you would want, not to mention Comprehensive Perl Archive Network (CPAN). CPAN is an archive of over 25,000 distributions of software written in Perl, as well as documentation for it. There are "plugins" for just about everything you could imagine. Integration to all the major databases, popular software products, and much more.
Python, Ruby, Lua, are other examples.
Another possible solution would be to run UNIX/Linux scripts on Windows. This can be accomplished with Cygwin. In short, Cygwin is a collection of tools which provide a Linux look and feel environment for Windows.