I just wanted to make sure someone was aware of this:
http://sol.gfxile.net/ddhack/
This may be of incredible use in your "porting" of legacy Windows games to Vista/7! I say this particularly because the source is available for further research/tweaks/extension. While this was intended for Wing Commander, some others have reported some success with:
* StarCraft 1 (slightly sluggish)
* WarCraft 2
* Fallout
* Fallout 2
Even more useful, is this ddwrapper10.zip - quoted from the page:
"DirectDraw wrapper DLL sources. Logs incoming calls to a text file and passes calls to the actual ddraw.dll."

While I'm sure it could prove useful for other Win95 games, I'm fairly sure that the games you listed don't actually have problems running on modern systems.

Starcraft and the Fallout games have messed up coloring on Windows 7 (I don't know if that extends to the GOG versions of Fallout).

It's easily fixable though with certain launch parameters, his goal is just to make that unnecessary. Which is nice.
I tried it with CnC and Red Alert and both froze at launch.

Starcraft was sorted out from what I've heard. Neither of my copies of Fallout have issues. But there's always DOSbox if some versions do.

Someone try this with Interstate '76.
Post results.

Actually, Starcraft is "fixable", i've played it recently on W7x64. ;)
The only thing i can't play, and wish to, is Dungeon Keeper 1, which craps out not due to DD stuff, but nVidias WDDM. The game 'works' [doesnt crap out] on XDDM afaik. I was checking out XP x32 drivers vs Win7x64 drivers.

The Direct3D mode won't work.

Well, as far as I understood from the readme, it's not a complete implementation, but rather one that is designed specifically to fix issues with Wing Commander 1-4.
ddhack is still at a very early stage, and may be somewhat unstable. It has
been mainly tested with the 'kilrathi saga' wing commander 1, wing commander 2,
wing commander 3 and wing commander 4 CD. If any other directdraw programs work,
it's a miracle!

Note that this is only for games that don't use Direct3D (i.e 2D games or software 3D).
If old games truly won't work anymore on Win7, there's always WINE which has a full OpenGL implementation of DirectDraw + Direct3D (up to DirectX 7, since DirectDraw disappeared afterwards) working with almost all games on Linux, which can easily be built for Windows (just the DirectDraw DLLs, not the full thing):
http://wiki.winehq.org/WineD3DOnWindows
edit: woops, the wiki says that there's a show-stopping problem:
edit2: and here is it already built:
http://www.nongnu.org/wined3d/

I doubt, but i'll check it out anyway. Desperate times, desperate measures.
I'll install DK in a moment, do the compatibility wizard's magic, and check this DD thing on DK D3D version.
Though, I think it's more of display drivers lack of old-stuff-support [that's 'legacy support', yea?] than DD. I don't remember how the game run on XDDM, but it went farther that on WDDM, but since i liked the Aero thingie, i've stayed with WDDM.
Gimmie some time for a bath and setting it all up, i'll get back to comment on the [lack of] progress. ;)
[edit]
Oh, it's for DDRAW, not D3D. So i guess it won't do much for DK...
Wine's D3D support for DX6 and DX7 is experimental and may be wonky. I've checked DK on VirtualBox, and the additions made it a bit problematic. The dynamic resolution+resolution scaling screwed the DK's 640x480 display [black screen when switched to fullscreen after launching the game, even though the music was running, and one could hear the menu clicks when moving the mouse, so the game was obviously working, the display went nuts], also the mouse likes to jump to edges out of the blue.

Well, I'm on my way to bed, but I'll check back in the morning to see what you've found out. I've played DK1 a bit in DOSBox, but it doesn't run smoothly, and isn't very enjoyable.

What excites me is not that it works for a few games, but that he's left some good code for us. The logging wrapper is a huge thing in and of itself, for those investigating issues.

DOS version had sh@t for brains, i mean, the AI. The Windows version was vastly superior. I played it 1.5 year ago on XP, learned a way to launch it without problems. Still, for Vista/7 x64, i guess we'll have to wait for a WinBOX or game oriented VMs.;\