Installs, then blank screen?

[dpblank]

I am trying to install Ubuntu 8.10 (desktop) on an eMachine - Celeron D processor, 80GB. I burned the .iso from OSX. The .iso was checked for errors on the eMachine, none reported.
Install seems to go correctly, yet upon reboot, I see the Ubuntu logo and orange loading bar for approx. 120 seconds, and then a blank (read: completely black) screen. Nothing more happens.

It should be mentioned that I have also tried installing Fedora i386, i686, and Ubuntu 8.10 (server), all with unsuccessful results.

The only possible explanations I could think of would be something to do with the eMachine's HDD? (Booting into Windows XP does a similar thing after start-up. The desktop environment is not accessible.) I am not trying to double boot, or anything fancy like that. I'd like for Linux to overwrite whatever is on the HDD. Another explanation could be I have the wrong architecture of Ubuntu. (Not sure how Intel Celeron D is classified? 32 bit? 64 bit? x86?)

I've been a Mac user for 12 years, so my noobery may be overwhelming.

Any thoughts, suggestions?
Thanks guys

[dstew]

Can you get the Live CD to run? Is that the problem you are having? Or is your problem happening on a system you already installed to the hard drive?

[dpblank]

No, the live CD will not run. At least I cannot make it run.
There is no working system on the computer as of right now.

[dstew]

Have you done the CD integrity check (opening menu item)?

[dpblank]

Yes, the CD reports error free. As does the Fedora memory test.

[CowzRule]

Does the machine have an ATI based video card?

[dstew]

Try booting in Safe Graphics Mode (another menu choice I believe -- press F6 for "Other Options").