You must have a BB data plan activated to get email and the BB browser. A regular data plan will not work.
I know of NO pay as you go BB data plan in the US on the major carriers, including ATT.
The Bold is a 3G device and I definitely would not call it "old-fashioned". You might offend a few BB users with that remark.
The speed depends on many things such as the connection, the device processor, device memory, distance to the tower, tower congestion and a few others. One really can't compare it to another device unless you are side by side, going to the same site at the same time. The Droid is newer, on a different network etc. Don't know the other specs, don't really care. And a video can be edited.
And before you buy a used BB, make sure you read this from our FAQ. It offers good advice for any used BB, from eBay or elsewhere: Buying a BlackBerry off eBay - BlackBerryFAQ