I recently tweeted that I thought the SyntaxHighlighter is the best way to display code on your blog. In response, I had some who were a little confused how to get started with the tool. The tool isn't as straight forward as some other tools. There are several steps you will need to take in order for it to work on your blog.
I plan to start using SyntaxHighligher from now on and I would recommend it for bloggers that post a lot of code, but if you an occasional code poster, then one of the following Windows Live Writer plug-ins might be a better solution for you (they are much simpler and faster to render and takes no setup on your blog). All that said, you might even like the plug-ins better than SyntaxHighlighter... and hey, that's fine by me :)
The Windows Live Writer plug-ins that I recommend are...