Sixty gigabytes don't amount to much in this day and age. That's the size of the drive that comes stock in the 13-inch (white) MacBook. So it's likely you'll want to replace it for something larger and, possibly, faster. Here's a step by step guide for do
Newer portable Macs use safe sleep (hibernation) in combination with normal sleep (older computers can use this, too). What happens is that when you put your computer to sleep, the system writes the contents of RAM into the file /private var vm sleepimage