Go to a local shop and ride a few. There is a lot out there, and much has changed in the last decade.
When I bought my last mountain bike, I went in with ideas for what I wanted, and I walked out with a different bike altogether.
Have fun, and don't worry about the cash outlay SO LONG AS YOU USE IT. Think of it as a per day cost which goes down each time you ride it. And, think of the money you save when you ride it because you are not spending money doing other things.
My 2 cents:
--Front shock necessary.
--Avoid rear shock unless you can lock it down, or unless you are downhilling. Rear shocks will slow you down on the uphills pumping all your energy into a spring instead of a sprocket. Front shocks do the same, but less so and they are worth it.
--Make sure your feet are secure in your pedals. Clip or clipless, just get comfortable shoes.
--Bar ends a must.
--A helmet. If it wasn't in style then, it is now. Wear it.
--A bell, a basket, and a kickstand. Steal a cloths pin and a card for the spokes.
Ski, Bike, Climb.
Resistence is futile.
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