the answer is definitely utah.
lets go through your requirements one by one...:

1) A lot of terrain, though not all triple black Something on
order of 2500-3000 acres.

within an hour from downtown salt lake are 5 resorts with more than 2500'
vert:
snowbasin, snowbird, deer valley (no snowboarders tho), park city and the
canyons.

there are also 4 resorts with more than 2000' vert:
solitude, powder mountain, sundance and alta (also no snowboarders). plus
brighton at 1750' vert.

2) Someplace where everything is *NOT* left bumped. I ride bumps here
and there, mostly late season. Yes, I'm not that good at them and my
rebuilt knee isn't fond of them in mid season.

like anywhere the more popular resorts get tracked out quicker. brighton,
solitude and powder mountain are the three resorts i stick to when it hasn't
snowed for more than a week. there are tree stashes and easily accessed
backcountry available via all three. in my experience snowbird gets tracked
out the quickest, but its also the steepest, so it lures the fanatical
hardcore to itself when it dumps. its a known utah phenomena. *shrug*

3) Decent quality snow, and at least some snowmaking for the lean times.

utah has the best snow. period. almost nobody (except deer valley, heh)
uses a lot of snowmaking. they don't have to.

4) Other mountains within a reasonable distance.

see the above list. plus theres beaver mountain about 2.25 hours away, and
brianhead about oh... i dunno... 3 hours away. hell, jackson hole and
targhee are less than 5 hours away. aspen and silverton roughly 6 to 7
hours away. theres nordic valley in ogden canyon, but the least said about
the place the better.

5) Hopefully not a total zoo every weekend

hmmm... the least visited resorts are definitely powder mountain and
solitude, in my experience. if you don't want crowds, you go there. maybe
sundance too, i dunno that much about their crowds as i've only been there
once.

Off hill,
A) Halfway resonable prices nearby the mountain. I don't have to be
slopeside! But would like to be inside a 20 minute drive. A small
house (A frame?) with some property would be cool

if you live in salt lake or one of its "suburbs" then housing can be very
cheap. if you live in one of the remote areas, you can get some land and
still keep it cheap. if you want to live in park city, or the cottonwoods,
expect to pay for it. ogden valley near powder and snowbasin as someone
suggested is a good compromise as you can still get some decent land up
there for a reasonable price. although its getting developed quickly, which
means the price is going up.

B) Some things to do locally outside of boarding. Movie.. more than one
bar.. food.

all of the above. and more.

C) High speed Inet for work (I work online out of home)

theres dsl, cable, and even highspeed wireless in some places. do *not*
count on it tho, in the canyons or more remote areas.

D) low crime, no quality of life issues (ie, Rudy's been there)

i'm from detroit, and salt lake and its surrounding environs are so safe as
to become almost boring to me.

As I would be spending at least 4 months a year there the offhill
requirements are a bit more important than they were when I took a
condo up in VT which is a short drive back to my home in NY.

So.. what do you guys think? Which mountains are good fits?

okay, then heres one closing thought. where do most snowboard and ski pros
live?
its usually one of two places. utah, or whistler. tahoe is a distant third.
and theres a reason for it. the reality is that more pros live here because
this places is a great combination of *easy* access to *great* snow.
period. thats why i'm here.

we get the most snow.
we get the best snow.
we have the best access to the greatest number of resorts.

bada-boom! done deal!

thats my spiel. don't flame me please. its just my personal opinion.
good turns,
paul