For what its worth, the DV2000 series of HP laptops have a common issue
with the video chip in these. I have reflowed many motherboards to
correct the connection problems, but the DV2000's do not seem to
holdup. I have also reflowed a lot of DV6000 and DV9000 motherboards,
and I can get them to stay fixed if I improve the heat sink contact on
the Nvidia chip, but the DV2000 have come back to me repeatedly.

This issue may or may not be related to your issue. I don't know.

On the face of it that system should be great for 12.04 so how does it
look if you use the 'Try Ubuntu' option from the boot CD. Also is this
the 64bit version or 32bit ?

If it works OK from the 'Try Ubuntu' option then try installing from
there and let it take over the entire HD again ( i.e. erase the
current installation that's not playing ball ).

Did you try Mint Linux or any other Linux Live CDs to see if the hardware is
still okay?

It sounds like a driver issue. I am not familiar with model, but Nvidia
drivers can be tricky. The initial installation with the venetian blinds
effect was probably Ubuntu's attempt to install the Nouveau driver which
was not cooperating with your hardware. The second attempt with proprietary
drivers was likely a Compiz issue. It is the window manager for Unity,
Ubuntu's desktop. I would suggest that you test it by opening an Ubuntu 2D
session from the login screen (click on the tine icon to the right of the
password box. Choose Ubuntu 2D. It uses a different window manager. That
works just like Ubuntu (more or less). That should get you working. If it
does not work then it is still the wrong driver.

You *can* change grub to use vesa all of the time by adding a boot
parameter. Grub is just a text file that you can edit with root privileges.

https://help.ubuntu.com/community/BootOptions
www.dedoimedo.com/.../grub-2.html#mozTocId624480

This should solve the problem of having to go into recovery mode.

Just to follow up what Ardell Faul was saying, I had a dv9000 a few years
back that had a similar issue. I had it set up to dual boot WinXP and
Ubuntu 8.04 I believe. I started getting lines on the display as you
describe, but only when I booted into Windows. Windows finally stopped
working completely, but I could work just fine with Ubuntu. Because Ubuntu
was working and Windows was not, I had also assumed it was a software
issue. After about 6 months, Ubuntu showed signs of failing as well, and
finally died. When I researched more, I found as Ardell noted that there
is a problem with the video chip on these motherboards. The heat sinks
were not designed to properly cool the graphics chip and after a relatively
short period of time, the solder points loosen and need to be reflowed.

A new motherboard would have cost about $300, so I did some research and
found a time/temperature chart for solder reflow. I bought an infrared
thermometer, made a heat shield out of an aluminum can and some tin foil to
protect the rest of the motherboard, and then used a heat gun and a timer
to reflow the solder on the chip. I also bought some thin copper sheet to
improve the contact with the heat sink and cut it a little larger than
necessary to help disperse the heat better. I figured, hey, if its already
broken, I can spend $30 to try and fix it, or $300 for a new motherboard.

After I finished the process, both the Windows installation and the Ubuntu
installation worked like nothing had ever happened. I got another 3 years
out of this computer before the same thing happened again. I tried to
reflow again, but I think I toasted the chip. Oh well. I was ready to
move on by then.

Thanks to everyone for their suggestions. The answer, on my computer, was to go
back to the 295.33 Nvidia driver as suggested here
askubuntu.com/.../unity-3d-no-longer-works-after-installing\
-12-04>.