Thinking of buying a 01-06 Yukon/Tahoe--???s

[jdurant]

Hey,
My wife has been driving around a Scion Xb for the last little while. I originally bought that a few years ago when I was driving all over town for work. I've been wanting to get her in something a bit bigger/nicer/more GM really for a while now. I was given the proper motivation the other day when a dude rearended us and knocked us into the car in front. Everyone was ok, but I do believe the little scion is gonna be a total loss.
Anyway, like the title says I am looking for a Yukon particulary(just because I like the grill a little better in this generation). But if I found the right Tahoe that could work too. I could find myself in the right Denali too. So here are my questions.

1. Is there anything/years/options that I should stay away from? Plenty of clean 01-02s out there was looking at the earlier ones to save a bit.
2. Not all Denalis are AWD, correct?
3. Ideally I would rather get a non Denali (because I don't particularly like the Denali bumpers or sidestep molding thing), and put the Denali grille and/or headlights in. Any problems with that? Should be pretty straightforward, right? Can I use just the Denali headlights on the standard Yukon grill, or the standard headlights with the Denali grill?
4. I should be able to put say 09 GMC wheels on it, no problems, right?

I think that is all for now. Thanks in advance.