Ditto on keep your pack - keep your pack and ignore the old school looks from
people who insist you have to have a 400 dollar pack to go hiking.

Once you get into it, and get your gear list down a bit to where you are comfortable
buy a pack that fits you and your gear. Have a look at the gear lists on this site, esp
the 27 pound 7 day pack and the 18 pound 3 day pack, as well as some of the others posted here (click my name to see mine)

As for bears, I personally wouldn't worry too much, in black bear country I seldom bother
with anything. I carry bear spray in grizzly country.