8.04 LTS Desktop Edition - Installer Woes

Complete Linux newbie here; I recently ordered a ubuntu 8.05 LTS Desktop Eidition cd; I have inserted the disk and booted from it and have tried the "try ubuntu" option; it loads the ubuntu logo and the progress bar fills up; it then proceeds to a testing stage; it get's to the stage after checking battery state... and the stage after the battery and all preceeding it report [OK] but it hangs as no tests are performed afterwards, although i can type but nothing happens other than the characters appearing on the screen.

I then tried the install option (boot from disk) and it did the same; but it got to a point where it flashed and a load of text came on the screen and it went to a bash console; fairly sure it isn't supposed to happen (graphical installer should load surely)

I then tried the install inside windows option; it also did what the above stage did; except it copied the files correctly.

I have the following hardware configuration:

Intel Core 2 Duo T5550 @ 1.83 GHz
2 GB DDR Ram
ATI Radeon Xpress 1250 - GPUz reports 1200 series; tho' card is 1250
GPU (GPUz) reports RS600M

I have absolutely no idea why it isn't working... please help :)