I have Mandrake 9.1 running on a PII-200 laptop with 128 M of RAM or
so.  While it is by no means a speed demon, it gets the job done.  For
the duties you indicated, this may be a decent distro.  
One thing you may want to look into for snappier desktop response is
IceWM instead of KDE or Gnome as your display manager.  IceWM works well
and in a much smaller footprint than the two big contenders.  You can
use it along with apps from both as long as you install all the
necessary libraries.
Good luck in your hunt.  I hope this helps.
Rob