Perhaps someone will prove me wrong, but you sound like you aren't much into the sport yet, and aren't doing anything to insane, I'd recommend a Gary Fisher Marlin. Its not fantastic, lots of midrange components, BUT I feel its a great starter, I love mine, and it should handle most anything you can throw at it as far as singletrack goes. I picked mine up for about 500 new, but remember, ride everything your LBS will allow, find whats right for you!

Yes. Obsolete. As in "let me sell you a $1500 bike instead of a $700 bike."

$500-$700 hardtail from one of the big companies, and use the money saved to buy a nice wheelset for the trails. slap some street tires/studded tires on the stock wheelset and you're golden for all occasions.