[NotationUser]

I think yes.

Just I don't know when its appropriate to ask as your installer is meant for all windows platforms but my experience is just limited to Vista 64bit... Asking all users all the time on any platform will for sure lead to many support questions when to select running as admin or not...

What Vista normally does is it throws a dialog box by itself if you run an application (including installers) that requests administrator rights. So the program does not need to show up any dialog by it's own. But if you wish to do so that will be the "kind" solution - I expect the Vista alert to pop up anyway - except it is disabled in general - which is possible too if I remember right.

I am not sure if I can remember any installers not requesting admin rights and if there were any these were so rare that I didn't notice...

Granting admin rights can probably be risky with software one does not trust. But on the other hand Vista 64bit has some kernel hacking protection that makes it even difficult for some security software (like Sandboxie) to provide full control and protection. I am really no expert here but my guess is there is something special with 64bit to take into consideration too.