For strings, see: http://wiki.freepascal.org/String
Either explicitly define the type as being an ansistring, or set that switch.

For parsing XML, it's all up to how the XML file is structured... assuming you have only that line in your entire XML file, I believe you'd have something like "YourNode.Attributes.Item[0].NodeValue".

I haven't played with XML in a while so I'm not quite sure. But basically have a look at the section "Printing the names of nodes". If you're still struggling with how it all works, simply compile that example yourself and look at the example.

You're not the only one who uses Tiled. As I said, I use it myself, but I just choose not read the file as XML.