[ubuntu] Live CD- Ubuntu 12.10, Ubuntu 13.04 Beta, Live USB Ubuntu 12.10- all fail to install

Hey guys!
I hope you'll be able to help me solve this problem.

1) I had Ubuntu 12.10 installed on my PC, but after I did an upgrade through the PPA repository, I messed up a lot of stuff, and I decided to re-install Ubuntu.

2) Live USB refused to boot.

3) Then I used a Live CD of Ubuntu 12.10. Here's where the problems started. The installer crashed repeatedly, and could never complete the installation. Many a times, the Live CD did not boot, and a message came up saying- 'Fatal Error: reverted to Text Mode' (something of that sort).

4) Same problem occurred with Live CD of Ubuntu 13.04 Beta 1.

5) On using the desktop directly through the Live CD, multiple crashes occurred, and before I could even reach GParted, the Live CD crashed, and i was forced to reboot.

I have gone through the same process many times- and I wonder what the problem is.

I even used a external CD drive, and encountered the same problems again.

My PC Config is:-

Intel Core 2 Duo 4400 @ 2.00 GHz
Intel 82945G Express Chipset
160 GB Seagate Barracuda HDD
3 GB RAM (By the way, my RAM was recently encountering problems- I fixed the issue just yesterday.)

PLEASE HELP!!!
:confused::mad::confused::mad::confused::mad::conf used::mad: