When xemacs installs on NT, it offers to register itself as the
default editor for c, java, ... files. However, it doesn't do a
complete job. In particular, it doesn't register for the ".cxx"
".hpp" or
".hxx" extensions. 
One thing even more annoying that how many extensions c++ programmers
use is when they open up in something other than emacs :-)
Suggestions - 
1. the simple:
   Register for those types as well. I can't imagine those are used
   for anything other than c++
2. the complete:
   Put up a dialog box asking for which extensions to register
   emacs. Emacs, being gods own editor, is useful for so many file
   types (perl, python, html, xml, batch, ...) that power users could
   well like to pick and choose from a larger menu.
3. the sinister:
   Run through the registry and snarf all the file types visual studio
   has registered for.
-- 
 Brady Montz
 bradym(a)balestra.org