Wow, I have to say I am perplexed by the lack of response on these ideas.

I suppose everyone who was looking for these solutions must have switched to WIN 7 long before I.
Certainly, Excel, Word, Adobe, etc. can be made to open both in AC and in their own application.
Microsoft, as they often do, e.g. not allowing certain files to be attached by default because we're too stupid to know better, locked this feature down in WIN 7. But, it still can be done using the registry. Just takes some poking around. I am not going to do it, because I have no need to.
But, if you are using XP or earlier, it's simple.