Hi SlCuster,
Yes, first look at the Status Report sample - it does this kind of aggregation.
For your report, you'll want to use A->B merge which is what we call it when you merge a form with a different schema into your form. Each individual form may not repeat at the root node. But, schema B will, or may differ in some other way.
You can either write code to do the import or an XSL. Visual Studio 2005 has a much better support for writing XSL and we recommend that. For the code sample, take a look at Jim Cantwell's HowTo on passing parameters. It's related.
Good luck and let us know if we can sell you a few hours of dev time. :)
Patrick Halstead
Project Manager at Qdabra