To install the Intel graphics drivers on an already installed recent version of ubuntu, I think you can :
The failure or success of this is unknown to me, as I do not have an Intel Graphics Media Accelerator. I find Nvidias better if having to install binary drivers.
sudo apt-get install xserver-xorg-video-intel
There have been problems/issues with Intels graphics drivers in the past:
Here, Here, Here,
and Here !
If you visit the Manafacture of the chipset you can see, it appears to work.. intellinuxgraphics.org and Intel G FAQ, although how you would ensure the graphics driver stayed working while correcting the kernel modules/drivers I wouldn't know. You would be immediately plunged in the dark if there was any problem.
You are always going to have such problem on a integrated chipset no matter what version of ubuntu, but you are not going to know what problem you may have until you try upgrading.
The first versions of Ubuntu 8.04 (LTS) had timing issues with some chipsets, but there have been three upgrades of the ubuntu 8.04 kernel since is release, so sholdn't be so much of an issue.
Saying 'about ata stuff not being found' could be a timing issue, but could also be something else, its not so descriptive. Saying 'couldn't get things to work' isn't so descriptive either.
Ubuntu Linux 8.04 is supposed to be a long term service edition and should be more stable.
If video or audio being played is crashing the session, you should have some files at /var/log particularly of the xorg/Xorg.0.log/dmesg type logs that should provide some clue as to why the session crashed.
Check there and check your BIOS for settings related to the onboard graphics card to see if you can change anything there.