Vista - changing display settings

I have an Acer Aspire L3600 which came with an Acer 19"LCD monitor. The
L3600 MoBo has onboard graphics identified as Intel (R) G33/G31 Express
chipset Family.
The monitor can display at 1440 x 900 but I often want to use a Dell through
KVM switch that can display at 1920 x 1200.
I've downloaded the Dell drivers but am not sure if they've been properly
installed.
The problem I have is that the Dell regularly changes its display to 1024 x
768 if I switch between PCs. The only way it seems, of restoring 1920 x
1200 is to click on the Dell download - Dell_2408WFP_A00-00_R172933 which
unzips 4 files - an .ICM; .INF; .CAT and a .TXT file into a
C:\Dell\Driver\172933. A reboot then shows display settings which extend up
to 1920 x 1200.

I want to make the 1920 x 1220 setting the deafult setting. How do I do
this?

Will any changes affect the settings on the Acer monitor when this is used?

Do the Dell drivers have to be installed where the others seem to be in
C:\Windows\system32\Drivers (or just C:\Windows\system32)?
TIA
Bill