Unable to install 11.04 onto Vista laptop

I have inherited my sister's old laptop, a Dell Inspiron 1501 (old version) that runs Vista Home Basic. I have a system image DVD of both Lucid and Natty, and have been unable to install either system (I tried Natty first, and when that failed, I tried Lucid). I was successfully able to instal Lucid onto my desktop PC with the same disc.

When I boot from the DVD drive in the laptop, the BIOS description tells me I am opening Ubuntu (or booting it rather), and I am able to make it to the load screen (blank except for "Ubuntu 11.04" on a maroon background). After that, I am greeted with an essentially blank screen that resembles a "testing" screen on an old TV (Vertical lines of color), and am unable to get the computer to respond unless I remove the disc and restart.

I spoke with a computer repair friend and they thought it might be a graphics card issue? I would really like to resolve this, as I want Vista off of this machine!

The laptop has a Mobile AMD Sempron processor 1.80 GHz, and 1 GB of RAM. Graphics card: ATI Radeon Xpress 1150