Hi Steve:

Snagit has what they call "Profiles". On the main Snagit screen they include some common ones. The one that converts to Text uses a full window - you can't highlight just a region (ie. the address).

You need to create a new Profile in which you select i) Region rather than Window and ii) option to convert to Text. There's a wizard in the upper right-hand corner of Snagit. It's very quick.