Go to an actual archery store to get fitted and try some out; read reviews in Bowhunter magazine. A lot of the differences are pretty marginal for new users. Current bows have a pretty amazing drop-off rate, which makes it very easy to hold at full-draw. But you do need upper body strength the get to the drop-off point.

If you’re talking real, serious, the-end-of-the-world-as-we-know-it apocalypse, then I’d recommend getting either a fiberglass recurve bow in the 80#+ range and a few spare strings, or a Mossberg Shockwave and a single shell. The fiberglass recurve bow will be difficult to learn to shoot effectively, but it essentially maintenance-free. The Mossberg will prevent you from having to learn to use the bow effectively.