> Can anyone help? I'm running Windows XP if that helps at all.

One solution is to run the program from the command line - so fire up a 
terminal, and type

ruby my_program.rb

in the directory where my_program.rb is.

One more thing - you need to ensure that ruby is on your path. I did 
this a few years ago for the last time, but I vaguely remember that it 
can be accessed through properties of my computer and there environment 
settings or something like that.

I am sure people on win32 can provide you better help than me, but until 
then you can experiment with this :)

Cheers,
Peter
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