I'm getting more into HU coming from 6 max. I know my question is player dependent, but how much of my range should i be opening IP and defending OOP vs a typical small stakes opponent?

Depends on the rake and the opponent. With weak opponents it can still be profitable to open raise 100% OTB even with the increased rake. But you could start out opening about 90% and defending 85% or so and adjust as you feel comfortable.

yea latefordinner just nailed it, not need for any more responses even

Out-of-position with deep stacks, I wouldn't tend to defend more than 40% of the time as it will be hard to play back on many boards. On the button, you should open nearly 100% unless your opponent is playing very aggressively.

This is a Limit forum. Just FYI.

OP, you can find Cepheus' BTN/SB strategy here, and that also includes his strategy facing a BTN open from the BB. Against "no actions" (aka Cepheus making the first decision OTB), Cepheus plays almost ATC. It plays any PP, any 2 suited, and even crappy offsuit hands like T5o. Its inflection hand is T4o, and it prefers a fold for J2-32, T3-43, 94-74. It actually defends its BB wider, electing to fold only 82o-32o, 83o, and taking a mixed strategy with 92o and 73o. It also takes a mixed strategy for light three bets, electing to do it sometimes with showdown value hands (A4s, 33), other times w/ hands that can smash flops (98s).

Edit: Just noticed this is a thread bump from 2009. Whatever, posting stuff on Cepheus is always fun.

I am mistaken. I thought this was a no limit forum.

Thanks for posting this. It seems very weird to me, but interesting.
Firstly, that it defends more hands than it opens. And secondly, even after having played infinite HU LHE hands myself, I find the hands that it chooses to do some things with somewhat baffling in some points. Like OTB it hugely prefers J3 and 104 to J2, 74 and 84 (all offsuit). Why?
And then vs a button limp, it raises 64o, 75o half the time, then raises 53s, 64s and 74s 100% of the time. Not comparing the os vs suited, but rather it's button opening range against it's raising range vs a limp.
So based on that, it seems like the play against it is to just limp the button a lot.
And then it 3bets 64s and 75s 87% of the time, and 74s around half the time (and the offsuit versions never). Again, can be compared to it folding 74o and 84o pre OTB always.
It generally it has quite a high 3bet %, mostly with including things like 95s, 106s, 107s etc.
Kind of a basic thing, but I would have assumed that it would want to be less aggressive oop than in position?
Does it take into account future post-flop position/playability, or just the value of the blinds pre?

Why is is surprising to defend wider than you open? You are getting 3:1 when you defend, infinite HU hands played or not

Regarding some of the other questions, for the large majority of flops, T high beats 8 high more often than not so act accordingly.