1) When I connect using the firstname.lastname@example.org, vzw, #777 settings, am I using voice minutes on my plan, or MB out of my (paid-for) PDA data plan, or neither?
2) This one depends on the answer to #1, but might I be able to connect using a dial-up account of my own (my cable provider gives dial-up access to its customers, and I have a direct dial-up VPN from my work) rather than the Verizon settings without using either my voice minutes or MB from my data plan?
1) You're using the PDA data plan.
2) I haven't used a dial up style connection to an ISP in some time on Verizon but I think it uses minutes from voice. I'd ask them to be sure. Keep in mind that dialup connections are much, much slower than the EVDO connection offered by Verizon (like 19.2k vs. 500-900k).