this is my first mac, imac. having trouble with my ehd, seagate. i use it for storage for my photos & music. when i use "GET INFO" on EHD my available space is 2GB. the problem is there are only 2 files on there, music & photos. if i use "GET INFO" on each file individually the combined space used is 79GB. the ehd has a capacity of 250GB. this ehd was initially used on my windows laptop. i thought i erased everything when i synced it with imac. this is most frustrating. i thought apple products were easy to use, user friendly was what they said when i purchased it. please help