Activation

[scottydee]

Hi, I'm new to the iphone and I'm picking it up Saturday, I'm just asking because I'm upgrading my contract and need help from someone in the UK on orange, if I have a normal sim card, do I need to ring a number to activate my micro simple or will my normal sim card just stop if I activate it like normal by putting the sim in and plugging it into itunes?

Thanks in advance

P.s- I'm a bb user and am really looking forward to getting an iphone if anybody could give me any tips, it'd be much appreciated