So there a few factors to consider here. You mention you would like to store things such as level name, level number and "game specific stuff". What sort of game specific stuff are you thinking? If you are planning on structuring your levels through XML files and then load them up on a per-level basis, it might be more tricky than it seems (eg. Saying this level has these 3 enemies of type B is pretty hard to convert into an actual object in C2). However storing things like level introduction text, random AI sentences etc. would be a good fit. So I'm curious what sort of information you would like to store?
Some other things to consider - XML can be a pain to manage. If you are just storing simple shallow data like this Microsoft book example it's not too bad - You can manage that with notepad++. But if you are planning on having deep nodes in your XML files like this slightly more complex example it can quickly spiral out of control. Also remember that any structural changes to the XML might render entire blocks of code in C2 unusable.
If you can post anything you can think of that you would like to be stored in XML, what problems you are hoping it will fix (that you can't do right now) and how you would like to use it game, I bet we could come up with some good examples how to structure your xml, some real-world examples to teach XML, and check if what your hoping to use XML for is appropriate.