Distros : Prep - Intro
Before I install Linux on to a PC I generally boot up with Puppy or similar to get a feel for the machine, see will the wireless card work, is there any important files that need to be saved, what way is the Hard Drive setup??

To get a detailed overview of a PC in Puppy use PupSysInfo: Right Click the Desktop and Click on System»Pup-Sysinfo System Information. Is it a 32bit or 64bit PC, and it's, drum roll, not 64-bit capable, so its a 32 bit PC, which have a decreasing number of Linux Distros available for it, not to worry, Debian is a solid option.

Opening a terminal and runningcat /proc/cpuinfo
orlscpu
will give you similar details.
Puppy has the tools you need to prepare a PC for an install, Gparted to set up the Hard Drive, A Web Browser to go to a Linux Disto Page and wget - a command line tool to download an ISO.
Puppy also has command line tools to check that the ISO downloaded correctly md5sum and to burn the image onto a USB key dd (use with care)
Never used a Linux Terminal before?? start here using commands to browse the file system and make Folders aka Directories, more»
If all you have is a single pc/laptop and a Puppy Linux disk you are good to go, prepare the hard drive with Gparted, mount a partition and use wget to download an ISO saving it on that partition. Check the ISO with md5sum and burn the image with dd. Boot off that image, start the Linux installer and you will soon have a proper Linux Distro up and running!!
So lets get started with Gparted »