I'm planning on developing an Windows desktop-based GUI application, and I don't have a clue which language or IDE to choose. I'd REALLY like something with a WYSIWYG GUI editor. My application will rely on web-based XML feeds, so built in support for that would be great. I don't want the application to have any dependencies or require admin rights to run. Cross-platform is nice, not not required.
I'm willing to learn a new language if that's necessary.