fitwxc,I wan to port my current cell phone

questions
1)my cell contract will expire after 2 month, can I port right now? or wait after 2 months?
2)can u port sprint phone?
3)I have a Verizon cell phone, want to port. Regarding roaming, I read from PP website, roaming fee is 0.59/minute. How do I know I am in roaming area or not? I checked Verizon map, my area covered by Voice & Messaging, but belong to roaming area for Verizon prepaid plan. So if I become PP customer, I just use verizon network which is covered by Voice & Messaging, so I will not charged roaming fee? Am I right?

Thanks!