Vista - XP Printer shared to Vista Laptop

I have a Desktop PC running Windows XP-Pro with an HP Photosmart P1100
printer connected. I have shared the printer. I also have a laptop
running Vista.
Initially I added the shared printer over our home wireless network to
the Vista laptop and was able to print using the printer. I believe
it was using printer drivers on the XP machine.
Then the CPU died on the XP box. The laptop became our only machine.
I connected the laptop directly to the printer and after trying to
install printer drivers for a long time discovered that the printer is
not supported in Vista. I found that if I forced the printer to use
an alternate driver I was able to get the Vista laptop to print to the
printer.
I then replaced the CPU in the XP machine and brought it back to
life. I deleted the printers on the Vista laptop and re-added the
shared network printer. Vista installed it using the "hp photoshop
P1100" drivers. I can only presume it still had the drivers stored
somewhere on the disc.
Now the laptop will not print to the networked printer. I presume
this is because it is not supported in Vista and is trying to use
local drivers. I want to get it back to the point where it is using
the remote XP drivers, but can't seem to figure out how to do that. I
cannot find the HP driver files to remove. When I go into the
printers window and go to server properties and tell it to remove the
HP P1100 printer drivers and package it claims to do so. But if I add
the printer again, it once again installs the driver - which must be
coming from a local source.

Does anyone know how to force vista to remove drivers completely and
permanently?
How else can I force Vista to use remote drivers for a network
printer?

Thanks for any help. This is driving me bonkers.