Blackberry's are awesome phones & you've chosen 2 great models. I used a Bold 9700 myself & i love my phone. I know alot of people who use the torch & absolutely love it as well. The touchscreen is quick & a great option.
Like all phones your Blackberry will freeze up from time to time, especially if your havent rebooted it in a while & installed alot of new software/apps.
As far as modems go, heres a great article to help you out.
[User] HOWTO: Use BlackBerry As Modem For Laptop! - BlackBerry Forums Support Community
Hope this helps!
