Hel me with my blackberry curve 8310 please?

i recently got my new blackberry curve 8310, and im to this company, vodafone, and when i cinfigurated it, in the email setup, i had 2 options, to choose a blackberry enterprise serves or not to chose it. i saw that heres another option to configurate your own email adress and i cant do that. another thing is that, after i installed the yahoo go, messenger for mobile, it says thati don't have connection to the internet though i downloaded it, or that my security has to aproove that... please help me :D:D:D if someones knows how to help -> bogdanitzagavrila@yahoo.com