Mountain Biking is something I've always kind of been interested in, but I never had a bike thats was good for anything other than riding to a buddy's house. I'd like to think I'm pretty athletic, I play soccer in the fall, and run track in the winter and spring. I also ride dirtbikes and I'm wondering if this would be something fun to do when I'm not able to go dirtbiking. I don't really know anything about the sport, so if you could just tell me what a typical day out for you is like that would be great. Also, whatever bike I got would be one of the Wal-Mart/Dick's/Dunham's bikes like mongoose or quest. I don't know if I'm up to the challenge because every time I rode one of the garage sale, suspension-less mountain bikes I had I ended up pushing it half the time because I either couldn't pedal up a hill, the ride was too rough, or the tire spun in mud. Would these things be fixed by a modern bike? My final question is how much does suspension matter? I understand that a front suspension is essential, but how important is rear suspension? Thank you for any and all help.

-Jack