i just recvd a new 500gb external hd that i have connected via USB until i got a sata card. it came formatted for windows NTFS so its pretty useless w/my powermac quicksilver. so my question is if i wish to use if primarily on my mac but sitll have the option to read (and write if possible on a windows system) what format option should i choose in disk utility. ...and by "format" i guess thats wha i'm doing when i use disk utility's "partition" function?