OS X/Cocoa includes some Emacs-style key bindings by default (see http://www.hcs.harvard.edu/~jrus/Site/system-bindings.html), so I don't think leaving other key shortcuts out makes the keyboard "interfere with a novice user" as you say. Dialog boxes don't support keyboard accelerators other than Esc and Enter, and the Finder doesn't support things like cut-and-paste or opening folders with the Enter key, and I find these things incredibly frustrating having used Windows in the past. Try doing something simple like moving a file from a directory to its parent in Finder versus Explorer.

More on the "Cocoa Text System": http://www.hcs.harvard.edu/~jrus/Site/Cocoa%20Text%20System....