well you can skip subD and go nurbs-Poly. I didn't try that to see if it'd work in keeping it as a whole object and not separate pieces but that can be done by Modify --- Convert --- Nurbs to Poly.
There are all kinds of settings in there that you could mess around with when converting to try and get a specific output.
group selection even from outliner will not allow you to mass edit the cvs or verticies of a set of objects as they are not all together. Grouping is simply a means for cleaning up and organizing the heierarchy.

As far as i have been made aware anyways...

-Cheers
-Alexander