Trying to Play an Old Game, will Installing Old Direct X Affect Anything

It's actually quite likely that these games are relying on old 16-bit DLLs. A lot of early 32-bit software relied on old 16-bit DLLs for some functions, as they did the job, they weren't used in a performance critical part of the software and there was no need to look for 32-bit versions. (for example until fairly recently the install software was often 16-bit, so much so that Win7 actually detects that and silently replaces with it's own 64-bit version of the old DLL).

Have you looked at Windows 7's XP Mode? This runs an entire copy of 32-bit Windows XP within your Windows 7, letting old programs run within XP without the program knowing it's on a 64-bit Win7 machine at all, and as it's all integrated you will hardly notice that it's running in XP.

Windows 7's XP Mode: what it is, how it works, who it's for

Some things to try if you haven't already (according to: http://forums.cncnz.com/index.php?showtopic=12319)

• Install DirectX 9.0C
• Run as administrator
• Set compatibility to Windows XP SP3
• Change the options.ini for Zero Hour, this is in a different folder than the normal generals options.ini.