Well, a 6th generation Civic VTi (1996-2000) already has the B16A VTEC (160 bhp) under the hood. Personally if I was to have a swap done it would be the B18C5 VTEC (195 bhp) from an Integra Type R. I would swap in this engine as it already produces 195 bhp and can easily be tuned to well over 300. Although this may be one of the most expensive Honda engines, it is well worth it.
Honda engines are very interchangable (assuming you have everything required), and although the newer K20A engines have not been swapped (to my knowledge) into an older Civic, it could be done. All the engines listed in the guide will swap into any Honda.
Other advice is look around for garages that can source and fit everything for you. That way you know you are paying for a full working engine, and an engine that has been professionally installed.
Oh, and I'd pick a Civic over an Accord. They are lighter, parts can be found very easily and they look better too.