Are you installing from a burned CD or from a bought CD? If burned, I would definitely check that first.
Also, if after clicking "forward" and it tries to get you to a GUI login, you may need to just reconfigure your X so that you can see exactly what is going on. Instead of killing the power, try pressing CTRL+ALT+BACKSPACE and see if it brings you to a command line. If it does then login as root and type the following:
Be sure to have all your hardware specs handy as you'll probably need them (monitor refresh frequencies, vid card info, etc).
If you don't get to the command line, try CTRL+ALT+DELETE and see what it does. Hopefully this will bring you to a command line. If that doesn't work, try pressing ALT+F2 to see if you can get to a terminal command line. If this doesn't work, post us back here.