[olimac]

Hello. I am absolutely new to the PPC device. I bought a used unlocked HTC 8525 have had it for a week. I have many questions which I hope you'll answer.
I downloaded the new ROM today Feb 28 2008 from htc america. Is it a good and worthy upgrade?if so, is it advisable to remove the sim card and the SD card before doing the update?
I have mainly contacts list in the device, so far when I synch it with my Pc does it back-up those contacts or do I have to send them to the SD card? Are my contacts back upped or do i need another program instead? i looked in the folder where it has the files in my pc but only found pictures , video but do not know where the contacts back up is.
Will the ROM update lock the device (GSM) again? I need it unlocked because I work in Afghanistan, but travel to USa and South America on break.
I am sorry if my questions might be primitive but I got this to replace a palm m125 and a old nokia phone so my knowledege is very basic and prehistoric PDAwise.