Hi, Jim.
Starting with Quicken 2010, Intuit has greatly simplified the structure of a Quicken "file". Previously, what Intuit called "a file" was actually a set of related files with extensions such as the ones you mentioned. Quicken knew to include the full fileset when we used options in its File | File Operations menu. Now, all those subsidiary files are included in the single QDATA.QDF file.
Now we can use normal Windows tools, such as Windows Explorer, to just right-click on the QDATA.QDF program file and Rename it there.
But I haven't actually tried that, so it probably would be safest to use Quicken 2011's File | Save a copy as..., give it the new name, and then load that new copy. Or use File | File operations | Copy... in the same way. When you are sure it is working right, you can delete the original.
Unless John Pollard has a better idea...
RC