Vista 64x/Ubuntu 64x Dual boot-new GPU installation

Hi All.
I'm running Vista HP 64x and Ubuntu 7.10 64x in a dual boot setup.
Currently I have an nVidia 8600GT but would like to upgrade to an 8800GT.
However the dual boot is causing me a problem.
NVidia forums advise me to boot Vista into safe mode, uninstall the 8600 drivers, run drivercleaner, swap the cards and then install the appropriate drivers from their website.
The problem is that since installing Ubuntu I no longer have a safe mode option in my boot menu. It has Ubuntu, ubuntu recovery mode, memtest, and then Vista/Longhorn. There is no safe mode option.
I can get into setup and BIOS (del,tab) and have looked in there but I'm not very techy and cannot understand it. There doesn't seem to be any mention of Vista after the initial choice.

Can anybody help me with some simple instructions? I want to upgrade the card to improve my gaming experience but it's proving complicated.
Do I really need to be in safe mode? If so does anyone know how I can boot into it?

Thanks in advance, John

No real need to do it from safemode unless you have problems, TBH I wouldn't even both to uninstall the old drivers (but thats not good practice)

1 Uninstall the old drivers.
2 Switch the PC off & swap the cards.
3 Start PC and install latest drivers from the nvidia website.

Thats all you need to do.

Thanks very much z. That's very reassuring and I'll now go ahead and order the card. Also have now discovered that if I keep pressing F8 I can boot into safe mode so wiil do it that way. As you say- best practice.
Thanks again, John

You got 4 displays?!! wow!