OK, I worked on that machine yesterday. I lost the internet yesterday also.
I looked in the BIOS to see if I could change the boot order but there was no way.
I tried to use Redo MBR and it gave me two choices, the old Linux install and the new one. Previously I had selected the old Linux install so this time I chose the new install. Reboot, still no entry for the new install and still the old grub screen.
So, I went through the install again. This time when I got to the grub installer I clicked the dropdown to see what the choices were.
This is what I got for choices
/dev/sda (followed by the name of the drive)
I believe the default choice was the first one.
XP is installed on sdb
PCLinuxOS 2009.2 is on sda
PCLinux is installed on sdc
I know it's probably not enough info but it's a start. I've never had a problem like this before so it's a new one for me. I just did this very thing on my machine a few months ago and everything just worked. My machine is identical to their machine. Of course, I don't have Windows installed on mine.
This may take a few days to get worked out because, unlike me, these people have a life and I have to work out a time to get over there. Luckily they live two houses down the block. They lost internet yesterday also. At least it's back now.