Use PERL, It's Free, runs under both
Windows and Linux (unix)
Modular
Interfaces with most Windows Applications
(if running under windows)
It's fairly quick
It's fairly easy to learn
It's what most of the internet's .cgi's are programmed in, so there are a crapload of
routines already out there to do almost all forms of math, reporting and anything else you may need to not re-invent