Wow, so the SIM card won't work on other phones? Dead SIM, get it replaced.
A working SIM card on another phone won't work on yours? Dead SIM Card tray; get your phone in for repairs.
Oh, and I forgot! If the phone you've got is not compatible with the radio network from your carrier, it won't work either (but even if this was the case, it should still be able to read the SIM Card, just not connect to any network).