Where can I see the chance for succesful hit (maybe THACO)?

You're to-hit roll (with all modifiers applied) must beat your opponents armor class (AC). That's it.

And what about the AC? Is it still like in BG (I mean the lower - the best)?

No, it's opposite now. The higher the better. It still starts at 10 for nekkid though; now AC 20 is the same as AC 0 was before.

I for one like the old system better.
there are a lot of things in 3rd addition that i don't like.

Wow! someone likes the old system of rules for D and D, never thought I'd hear that!

Yeeps, I've heard people say they liked this and that out of the second edition rules, but I don't think I've yet to hear anyone say they likes the mess that used to be thaco and ac. New system is so very simple and straightforward, but I guess if you've been a long time player, old habits die hard.

I used to be a staunch proponent of the oldskool rules. But I've changed my mind since playing 3ed pnp! I like the flexibility and the ease of play in the rules! Very, very nice! It's won me over!

I'm still a lot more used to the 2nd ed. rules, after being a BG2 addict for two years, but I'm growing to like the 3e rules more. The fact that any class can gain any skill seems a lot more realistic to me, and being able to class over without losing your ability to advance is pretty nice as well.

I never really knew the 2nd edition rules very well and now that I have had time to learn the 3rd, I like them a lot better.