Travelling Settings on Verizon iPhone

I'm hoping someone can help me with my phone settings for an upcoming UK trip. I spoke to Verizon, but didn't get a clear answer. I purchased a plan for use in the UK that gives me 100mb's of data for $24.99. What I'm not sure about the roaming. I'd like to be able to make a call or receive a call while I'm there, without raking up roaming charges. The Verizon rep told me calls will be $1.29 a minute, which is fine as I'll make very few calls.

Any help will be appreciated.