Hello,
If that formatter tool does not work - most likely your SD card has gone kaput. You can only write to them so many times - as they do not last forever (just like the engine in a vehicle).
A 2GB SD card probably goes for less than 5 bucks these days (if you can even find one as small as 2GB). Heck they even throw in a "free" 8GB SD cards in certain Radio/DVD combo players.