Every version/edition of Windows since XP has been NT-based. XP is actually NT5.1, Vista is 6.0, and Win7 is 6.1.Kurt Rahn wrote: Quick hint: You might want to consider NT, not 7. NT is very stable (it's what I use on Fusion on my Mac) and I've heard the consumer versions of Windows (e.g.7) aren't so much.
Answer to your question, 64 bit version of Windows allows more data throughput, so theoretically it's faster. However the software your're using has to be written as a 64-bit version to take advantage of the additional throughput.
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64-bit offers no performance advantage until you need massive RAM for working space or caching (i.e. high-end workstations and servers). That said, I wouldn't do a new 32-bit install since 64 bits is gaining in popularity and there will eventually be a program you want to run that is 64-bit only, of only because the publisher doesn't want to compile and support a 32-bit version. But even on a machine with 4GB or less, 64-bit operating systems use memory in a more linear and cohesive way than 32-bitters. In 32-bit Windows, all running applications get 2GB of RAM to use (even if you don't have 2GB for each app, the OS makes sure the apps see it that way) and the OS will only use 1GB for file caching. A 64-bit OS eliminates the file caching limit and eliminates the 2GB/app limitation for 64-bit apps.
If you're the type that likes to re-install your OS every year, then install anything you want now because you'll be re-installing before it's an issue. My Windows installations end up becoming developer workstations and I grow deep roots into them with lots of tools and utilities and it takes a couple weeks to get back up to 100% on a new install so I usually go at least 2 or 3 years on an OS install.
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