Linux rescue software Live CD
http://ubuntu-rescue-remix.org/
Ubuntu Rescue Remix is a GNU/Linux live system which runs from CD or USB flash device. It provides the data recovery specialist with a command-line interface environment equipped with the best free-libre, open source data recovery and forensics tools available.
http://www.knopper.net/knoppix/index-en.html
Live CD based on Debian. Knoppix, which is a complete bootable Linux on a CD, has become my rescue disk of choice. Knoppix runs entirely in memory, or if you want to sound "leet," in a ramdisk. In fact you can see the ramdisk in the file tree.
http://gparted.sourceforge.net/livecd.php
GParted Live is a small bootable GNU/Linux distribution for x86 based computers.
It enables you to use all the features of the latest versions of the GParted application.
GParted Live can be installed on CD, USB, PXE server, and Hard Disk then run on an x86 machine.
Included Packages
GParted Live includes additional packages, such as:
mlterm - Multilingual terminal emulator (provides access to command line)
partimage - Backup partitions into a compressed image file
testdisk - Data recovery tool that can help recover lost partitions
nano - Text editor
vim-tiny - Enhanced vi text editor
parted - Partition table editor (command line based)
fdisk - MSDOS partition table editor (command line based)
gdisk - GPT partition table editor (command line based)
http://www.f-secure.com/en_EMEA/security/tools/rescue-cd/
If your computer no longer starts due to malware corrupting the operating system, or you suspect the security software has been compromised, you can use the F-Secure Rescue CD to securely boot up the computer and check the programs installed. The Rescue CD can also be used for more advanced repair and data recovery operations.The Rescue CD contains Knoppix (a derivative of Linux), an operating system that runs completely from the CD and allows access to your computer's Windows operating system and hard disks. Note: the Rescue CD cannot scan encrypted disks.
http://www.gnu.org/software/ddrescue/ddrescue.html
GNU ddrescue is a data recovery tool. It copies data from one file or block device (hard disc, cdrom, etc) to another, trying hard to rescue data in case of read errors.

Comments
Hardware detection
* fdisk -l displays all partitions on all hard drives. is a useful troubleshooting and system discovery tool. To see everything, run dmesg with no options.
* lspci -v gives detailed information about every device and chipset connected to the PCI bus.
* cat /proc/cpuinfo tells exactly what CPU is installed.
* ifconfig displays, and also manipulates, network interface settings. Most commonly Ethernet cards and ppp, the modem interface.
* iwconfig is like ifconfig, but for wireless network cards.
* dmesg is interesting. man dmesg isn't all that helpful if you're not a kernel hacker. Just using dmesg | grep