How important are things like disc brakes, suspension, etc? What type of frame? How many gears? Anything else I'm missing?
I would not like to spend more than $400, so telling me I need top-of-the-line equipment is out. I'm also a beginner, so I will be using it for dirt-road type biking 2-3 times a week, building up to some bumpy trail riding. Once I get better at it (and decide it's the right sport for me, I'll get a top-of-the-line model.)
I'm a fairly big guy (6 ft. 200 lbs.) Any special considerations for my size?
What gear do I need? A helmet is necessary, of course, but what else? Gloves, shorts, ect? Oh, and I WILL NOT wear the tight shorts. Sorry.
Finally, please don't recommend a specific bike, unless you are using it as an example of a bike that has the parts you recommend. For example: "You need a XB500. It's awesome!" does me no good. Try: "You need an aluminum frame like the XB500"- that's helpful.
Thanks for your help!
For your price range, you should limit yourself to a hardtail, front-suspension only. A rear-suspension bike that is worthwhile will be hard to find in your price range. Make certain that you can set the pre-load high enough to deal with your weight.
You may be able to find mechanical disk brakes in that price range, but I would be inclined to stick with the V-brakes. If the added expense is used on discs, they've cut back somewhere else. My son's bike (KHS Alite 500) came with disc-compatible hubs and the necessary frame and fork mounts to retrofit discs at a later time.
You should get gloves, full-finger or half-finger, your choice. You'll appreciate this after your first tumble in loose rock. Shorts are not 100% necessary, but they'll definitely be more comfortable for rides of an hour or more. Baggy mountain bike shorts with liners are available from numerous shops and on-line retails.
You might want to consider shoes and clipless pedals. I would probably ride the trails a few times with the regular platform pedals to get used to the bike, but clipless pedals and shoes can make a world of difference.
Don't forget water. I tend to use water bottles on my road bike and a hydration pack when I'm riding the mountain bike.
You'll also need a small underseat bag to carry a multi-tool and a spare tube. You'll also need an inflator or pump to carry on the bike. You will get a flat sooner or later.
Other than that, get a bike frame that fits. Torso measurement is just as important as leg length. A bike with a top tube or stem that is too long or too short will make you uncomfortable and not be as stable.
Good luck.