A parent, who wants to purchase a GNT as a Christmas gift for his son, emailed me and asked what I would recommend. I recommend one of two options.
Reader’s Greek New Testament
There are several of these on the market, but in my opinion this one is the best. It is absolutely beautiful and provides both vocabulary and some parsing helps. There is no English translation, however.
Greek-English New Testament
Again lots of these on the market, but this is the best. On one side of the page you have the Greek New Testament beautifully typeset to line up well with the NIV on the facing page. No parsing or vocab helps, but it’s a great Greek-English edition. I would not recommend an interlinear. If you want something Greek-English, this is the ticket.
I own both of these and love them. The first time I read through the GNT it was with a reader’s Bible, the first edition of the one listed above. When asked for a recommendation, this is always the first thing out of my mouth. If, however, the plan is not necessarily to chip away at reading through the whole GNT and mastering the most frequent vocab but to simply have the Greek and English accessible in church, option 2 would be the way to go.