hard drive problems

[ITH]

while doing some downloading my computer started acting really odd. started freezing up and just doing nothing. i was downloading some newzbin crap. well after logging back on the next time my computer wouldn't recognize my second hard drive, the one i downloaded everything too. i don't know if its overfilled or it has a bad sector or what. anyone know how i can fix this? are at least retrieved data from it? cause the computer wont even recognize it so i cant access it. any help would be awesome, i got a ton of crap on there i really don't want to loose. thanks, honestly i think i might have overfilled it or something so if theres anyway to get on it and delete crap.