That's a prefect solution. There are a ton of langauges, but let's face it, there are BASICALLY 2 kinds. Basic, real. Basic is a fairly simple, and easy to figure out language, if, end if, etc. Then the real style (you know, C, C++, Perl, Java, Javascript, etc) with the cool braces and brackets. So, you just look for a list of programming syntax in their post, and either ask them to use code tags, or automagically add them.
Another solution, since some people have a hard time figuring out how to stick stuff between code tags, is to have Dani modify vbullettin, and have a link or another button for "post code", which loads a new window with a textbox, where they paste the code, and it adds it to the post with the tags.....