What are the differences between 32- and 64-bit Vista?

[I Am Herenow]

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[Husar]

Erm, Vista 64 should run most 32bit applications. Medieval 2 and some other games run fine on mine.
I don't know about security, shouldn't that be similar?
Things that don't run include flash(no 64bit compatible version yet) and some java applications seem to cause problems(some self-programmed game which runs fine in XP). Most incompatibility I've come across was concerning hardware, but I didn't install that many programs yet.

[I Am Herenow]

But would you recommend 32- or 64-bit?

[Husar]

I just have 64 bit and don't know exactly what could be better in the 32bit version.
Theoretically at least the 64 bit should be faster, CPUs are 64bit for a while now anyway. You might want to check for driver availability though, some drivers are only compatible with 32bit, so these devices may not run on the 64 bit version.

[Sigurd]

Consider this:
Do you have a computer with a 64 bit processor? if not you probably have a 32 bit system.
It is logical to me to use the respective OS to the type of System you have i.e. a 64 bit OS in a 64 bit system.
In short:
If you have a 32 bit system (CPU is 32 bit) use Vista 32, if you have a 64 bit system (64 bit CPU) use the 64 bit Vista.

You should know that a fully operational 64 bit system needs 4GB of RAM (anything less and you are not using it to its full capacity).

[Husar]

You should know that a fully operational 64 bit system needs 4GB of RAM (anything less and you are not using it to its full capacity).

You work for that local hardware store, don't you?
So does it run faster on my 2Gb than a 32bit system or should I switch?

On your argument about where to use which version, running Vista on an old 32bit system does work, but I'd recommend keeping XP instead if a system is that old.