Continuation of screen resolution problem in Ubuntu (Dell)

No improvement when I started Ubuntu on the Dell this morning. The best I got was 800x600 resolution. So, as I had reinstalled Hardy yesterday without formatting the /home, I now though that perhaps the problem was in /home.
So, I spent some time copying stuff that I needed to the Philips usb HDD (actually, why, given that I'm using usb 2.0, can I only get 22 MB/s (or 176 Mbps) from the Dell to the Philips via a simple usb cable when usb 2.0 is supposed to be able to provide rates up to 480 Mbps?).
In any event, I reinstalled Hardy with formatting of both / and /home.
After I had manually installed the nVidia driver (96.43.05) I got the 1280x1024 resolution. However, after a reboot it was back to either 800x600 or 640x480.
I began to think that perhaps my graphics card was on the way out but when I found that Windows XP on the same machine had no resolution problem I was somewhat reassured.
I tried a lot of changes in /etc/X11/xorg.conf but all to no avail.
So, I googled to see if anybody else had a similar problem. Sure enough, there seems to be some problem with Hardy, X.org and older nVidia cars. Many have had this problem although no quick fix is available.
Then I came across this blog page on this topic. At least two potential solution are suggested. I chose the easier one of trying the nVidia driver install using envyNG.
This is available in the Ubuntu repo (I used envyNG-gtk.
So, I ran this and away it went downloading, deleting and installing a bunch of stuff.
Then I rebooted -- looked good. After rebooting quite a few times it really seems that this is the answer I've been looking for.
However, I'm very unclear what exactly the problem was and why envyNG (but not the manual install of the 96.43.05 driver) did that was so much different. Remember that the problem seemed to start with repeated returns to the login screen yesterday. In addition, I had run with Hardy on this machine for some weeks without problem.
Perhaps an updated I loaded in to Hardy may have taken exception to my rather ancient graphics card.