As mentioned by Night Hawk, it's best to wait until the data is backed up. But don't wait too long, as you never know when the drive decides it's now a paperweight.
That would be the first priority especially if the drive is going belly up on you. I still find it hard to see where a second drive would fail however when the 80gb was the OS that would have seen the hard boot upon the OS crash.
On the other hand if the drive was already in the process of failing on you that might explain some of the original topic's source of problems since WE would have been having problems trying to read and write to the drive resulting in the "explorer not responding" errors.
OS Windows 7 Ultimate x64, XP Mode, W8 RP VM, Linux Mint Debian 2nd OS HD- 7 Pro x64 second case CPU AMD Phenom II X4 975 Deneb 3.6ghz - 965 on new mini tower Motherboard Gigabyte GA-790XTA-UD4 Memory Kingston Hyper X DDR3 1600 1.5v 16gb - Mushkin on 2nd build Graphics Card MSI HD Radeon 5750 1gb - MSI HD Radeon 6450 on mini tower Sound Card Creative Labs X-Fi XtremeGamer - Realtek onooard 2nd case Monitor(s) Displays 2 x Acer P191W 19" widesscreen - HP 20" widescreen mini towe Screen Resolution 1440x900 native - 1600x1024 on 7 Pro x64 build
Keyboard Microsoft Recusa Razor - MS Comfort 3000 on second build Mouse MS Trackball Explorer - A4TECH dual scroll wheel trackball PSU Corsair 750TX - primary / Corsair CX600 - second Case Antec 900-2 - SSD compatible / NZXT Vulcan mini tower Cooling Zalman CNPS9900A Hard Drives Primary Ultimate x64 build-
WD Black Edition 1tb Sata 6.0 = 2
WD Black Edition 1tb Sata 3.0 = 2 (OS drives)
WD 1tb Green Power sata = 2 1 external
usb flash drives = 18
Second 7 Pro x64 mini tower-
WD Caviar SE 500gb sata II single drive presen Internet Speed 30mbps upgrade - primary hard wired - mini tower usb WiFi