few iphone questions

[doox00]

I am thinking of switching from sprint to verizon, I have an evo right now, and like it very much.. I am just not all that thrilled with sprint service. I need to be able to tether in the field to my laptop for internet access, I need to do this through usb though, plugging the phone into the laptop, is this possible? I have read you can do it through wifi, but in my circumstance this is not an option. I assume you can jailbreak the iphone 4?

thanks all