Dying Hard Disk
Partition Find & Mount http://www.findandmount.com (This just mounts the partition, and you use windows to copy your files to somewhere safe)
HDD Regenerator http://www.dposoft.net/hdd.html (reclaim data from damaged blocks)
HDD Capacity Restore http://blog.atola.com/restoring-factory ... -capacity/ (some drives are limited in size, or have hidden partitions)
EaseUS Partition Recovery http://www.easeus.com/partition-recovery/
VirtualLab and iDriveRepair http://www.binarybiz.com (will salvage some data for free)
EaseUS Partition Master http://www.partition-tool.com/personal.htm (All-round excellent partitioning software)
HDD Guru http://hddguru.com (lots of resources and software)
Dead Operating System?
Ultimate Boot CD http://www.ultimatebootcd.com
Windows Ultimate Boot CD http://www.ubcd4win.com
(These boot discs contain the official Hard Drive tools from all the main drive makers.)
Bootable Linux Distros
Linux Mint is one of the most complete, with regard to using alongside Windows. It is able to read NTFS drives, and will bypass the Windows user passwords.
If you have an older, slow PC or not much RAM, then this little puppy is for you.
Notable extra tools
Disk Heal http://www.computer-realm.net/diskheal/ (Fix Windows OS based disk problems)
HDD Scan http://hddscan.com Easy and clear SMART based software, with a few other features. The site also has some useful info.
Here's a tip from my old bag'o'tricks for anyone who has a PC that will not re-spawn.
Easy If your PC has had no major hardware changes since installing Windows. (Windows allows 3 major changes)
1) Connect the drive from the dead PC to the new one, and boot into safe-mode.
2) Open the device-manager and delete everything (Some devices are hidden, and do not need to be deleted, but it will not hurt if you want to remove them).
3) Reboot, and log into admin or your normal profile.
4) Windows will now behave like you just installed it, and start asking you for the drivers it does not have (but you should have them already).
5) Run UT and kill something
Having suffered total total OS/MoBo failures, several times on my computing journey since 1982 (no grey hairs yet!).
I install my systems, assuming that they will fail.
The only things in the C: partition are the OS, CoDecs, browsers and a few support tools.
Everything else (including temp files) lives on separate partitions or drives.
I can completely move my system from 1 PC to another, within a few mugs of coffee
I am constantly surrounded by spare parts and screens with progress-bars, and my personal PC's reflect that. Always in a state of flux and ever changing, and I seriously can't imagine only using one PC at a time (that is a curse not a boast).