Hi, I have just built a new computer and planning on installing Vista on it. I have two questions about the Vista Ultimate 64bit Upgrade.

First, does the 64bit Vista upgrade require an existing 64bit OS like Windows XP 64bit, or doesn't matter? I have Windows XP Home which is 32bit.
Secondly, can 32 bit applications install and run in a 64bit OS? Like Office 2007, some newer games, Firefox, etc.
There is no price difference between the 32bit and 64bit Visa Ultimate Upgrade at the vendor which has student discounts and where I'm planning to make the purchase.
Thanks
New rig at stock speed:
Core2 Q6600
Asus P5N-E SLI
Crucial 2GB DDR2 667
EVGA GF8600GT 512MB
THERMALTAKE W0093RU TR2 500W
Old rig:
P4 2.4B
MSI 845 PE Max
1GB DDR 333
ATI 9800Pro 128
Antec 300W
Sound Blaster 5.1
First, does the 64bit Vista upgrade require an existing 64bit OS like Windows XP 64bit, or doesn't matter? I have Windows XP Home which is 32bit.
Secondly, can 32 bit applications install and run in a 64bit OS? Like Office 2007, some newer games, Firefox, etc.
There is no price difference between the 32bit and 64bit Visa Ultimate Upgrade at the vendor which has student discounts and where I'm planning to make the purchase.
Thanks
New rig at stock speed:
Core2 Q6600
Asus P5N-E SLI
Crucial 2GB DDR2 667
EVGA GF8600GT 512MB
THERMALTAKE W0093RU TR2 500W
Old rig:
P4 2.4B
MSI 845 PE Max
1GB DDR 333
ATI 9800Pro 128
Antec 300W
Sound Blaster 5.1
