unrevoked 3 roots the phone which makes you able to back up the original rom (firmware as i understood) and then install a custom rom - am i right?

and lets sat i have installed a custom rom and the phone has some problem, i need to revert it to the original rom before sending in to htc centre, am i right?

how am i supposed to do so... i dont see any tuts / procedures / steps anywhere

p/s: please do not flame me, i've been reading stuffs about rooting and installing custom roms elsewhere but none tells me how am i supposed to revert it back to its initial status

i havent got my wildfire yet. i am still waiting for stock, just that i want to know what i have to do before doing it, to avoid any irreversible thing from happening...

sorry to trouble you but can u list the general procedures in flashing a custom rom