That's a pretty varied collection of phones for consideration. It might help to narrow it down-- do you can lots about price, hardware keyboard, OS or any other things?
If you're into BlackBerry phones, the Torch is definitely sweet.
The HTC Surround is a nice phone with good build quality but it's a bit on the larger and heavier side due to the slider for the speaker bar. The Samsung Focus is our top pick for Windows 7 phones on AT&T right now, and it's got a great display and is thinner and lighter. Check our our review of the Focus to learn more. The new OS is pretty sweet, btw.
The Aria is a nice affordable mid-range phone with a "normal" design compared to the Moto Android mid-priced Android phones on AT&T. The Samsung Captivate is a nice high end Android (I know, I just added to your list!).