Considering the wealth of emulation options at the moment, I doubt that will be the case very soon. And x86 works fine on Vista and Win7, I don't even know what you mean there.
Open platform games without persistent connection requirements last damn near forever.

As far as I know, 16bit Windows apps flat out will not run on 64bit OS'es, no matter what you do.

I think it works if you run them in an emulator with a 32-bit guest operating system, even if the host OS is 64-bit

A virtual machine, you mean? Like VMWare? Might be worth a shot. The question is whether sound and 3D acceleration will work. If not, it's rather pointless.

I heard that this was going to be fee-free, Guild Wars style, and I was interested. Not that I hear that there will be fees, and now I'm not. That said, I might not stretch to 50 hours (I tend to stop around the 40 hour mark, although replacing my crappy PC may mean I might break through the 50 hour mark for TF2 and TrackMania United Forever. Still, 40 hours+ of entertainment for sub-£15 each, or in this case got Orange Box as a gift and got TM with Audiosurf. So that particular £15 would be pushing 60 hours of entertainment for me, and counting).
That all said, I approve of hours being used as the primary option, with a "days" option for the hardcore. More pay-for MMOs should use that option.

Yes, I meant to say a VM... You have to read what I was thinking, not what I actually wrote :P
Sound should work (the VMs make a virtual sound blaster 16 or something) but 3D acceleration probably won't. Were there ever any 16 bit 3D accelerated games though?

Yes, Dungeon Keeper...
*WAAAAAAH!*
I have to play the DOS version through DOSBox, and while it's playable, it's not pretty, and it doesn't run optimally. The controls feel a bit wonky.

Actually, come to think of it, VMware has working Direct3D acceleration for Windows XP guests. Don't know about OpenGL.
If the 3D accelerated version of DK uses Direct3D, and if it works in Windows XP, you might have a chance.

It does. The exe file is even called keepd3d.exe.
The weird thing is that only the 3D accelerated version is 16bit. The ordinary windows version (which is older) is 32bit. But that won't run either, sadly.

The problem isn't accelleration support, the problem is hardware emulation. I've never once seen a Virtual Machine emulate anything better than the level of an S3 Trio for the simple fact that they're designed for business apps rather than gaming.
Now if one of those VM makers were to make a gaming focussed VM and secure ATI/Nvidia hardware emulation (as plugin modules so you could swap virtual video cards and not have to buy a whole bunch of cards at once), I think they'd be onto a winner.
Hmm, now I can't speak for anyone else but I think that would be a brilliant product for GOG to make if they have the means.

Nope. There was quote from one of the staff that said it wasn't going to be subscirption based. Some people assumed this meant free (as I did).