Hi people!

My name is Francisco and i´m from Portugal.

i have a 3gs and i have a little problem: 1 have already created a apple id, and i go to apple store to download a free game, and when i click to download tells me that its the first time that i´m using that apple id and to tap review my account information. I go to the review and shows me that a must give my visa or master card.....?! i dont understand what´s going on...! to download a free game i dont need visa... Anyone could help me please? And could you give me some sites with nice apps please? thank you