Matt,
You might consider a double major. I would strongly recommend avoiding any majors in a practical theology field, but a major which stocks up on biblical studies, biblical languages, and theology (non-practical) would be acceptable. It would be okay to minor or take a few course electives in a practical theology field, however.
If you are seriously considering seminary, you should minor at most in Bible and theology at the undergraduate level. Seminary programs are designed for those who enter without any formal training in Bible, theology, biblical languages, or ministry. Some seminaries will allow you to avoid repeat courses (e.g., introduction to the New Testament, etc.). However, they often require you to take electives in place of these courses. Thus, you would basically be throwing your money away.
If you are considering missions works, I strongly recommend coursework in cross-cultural and/or intercultural communications. I have interacted with too many missionaries who are oblivious to this.
And, finally, a couple of potential majors you might look for as your double or even primary (if you go the seminary route) are instructional technology and (applied) linguistics. If you're a computer person instructional technology is a great field. It is the application of computer technology to "instruction" (or education). It is a hot field now, and it will only continue to grow. There are positions in academia and the corporate world. You can obtain positions with international schools. That could be your "in" for some countries, and does not always require you to draw support from a denomination or local churches.
Applied linguistics would be great because as a native English speaker you are in a high demand around the world. With a bachelor's degree alone, you can find an acceptable position within a week or two at different locations around the world (e.g., South Korea, China, Taiwan, Turkey, Russia, etc.). With a major or minor in applied linguistics, you become a relatively hot commodity. Plus, it's often possible to obtain a teaching license (with additional coursework) to work in public schools in the States. ESL (English as a Second Language) teachers are one of the more in demand skill sets amongst teachers today. (They do rank under mathematics and science teachers though.)
My personal recommendation would be avoiding a single major in Bible and theology. I would add something "marketable" onto that because I have too many friends who studied for vocational ministry and now only volunteer at their local churches. They have had to develop a marketable skill set without the coursework.
Hope that helps.