Can I use T-Mobile Dash to browse Internet without having plan upgraded?

[zmneuro]

Hi,

I am novice to smart phones, so please pardon my arrogance. I have a family plan with T-Mobile (NYSE: DT) and regular cell phones. I am thinking to buy unlocked Dash on eBay and to put a sim card from my current phone. (by the way, can you tell me if the Dash has hand write recognition, like palm?).
My question is: Will I be able, say, to go in starbucks or somewhere with Wi Fi Internet access and browse the web (Yahoo news and email) without subscribing to special internet service with t-mobile? I don't need to be able to go on web everywhere, jut is places like airports or cafes, to check my yahoo email, read some news and perhaps do some Google (NSDQ: GOOG) search. Thank you!