Any villager can heal someone. They might take a little longer than trained doctors, but they can still do it. Also, you can't heal someone who doesn't show "Sick" in their status, no matter how weak they are.

After you pause your game, HotSync, then go into the 'backup' folder for Palm desktop (usually \program files\palm (or palmone)\username\backup) and copy the file 'VillageSavegame.pdb' to somewhere safe on your PC.