Ignoring old harddrive contents

I recently erased one of my internals and installed Leopard there, and switched to it for daily use. I still have the contents of the old drive intact, with all my old applications and whatnot on it.

However, currently, applications on the old drive are still registering themselves or whatever with services, so I have files trying to open themselves in old copies of apps, I have 'Open with...' dialogs displaying applications from the old drive, and I have Quicksilver trying to open apps from that drive incorrectly. Is there anyway to ignore the old drive for these purposes other than simply ejecting it? I don't want to have to go to disk utility to mount the drive everytime I need an old file...

You can take this as you wish - am only thinking aloud here.

Not really sure I understand what's happening and am haven't been using a Mac that long. And I don't use Quicksilver.

Having said that, do you have Spotlight indexing that old drive?
(Or some similar preference in Quicksilver?)
This would cause all the old applications to appear in the dialogs and such.

Am thinking at this point, even after you add the old drive to Spotlight's Privacy tab, you may still have some old files trying to open in the older apps.

Or maybe it's just a matter of doing a "Get Info" of the individual file types from the old drive and changing it's "Open with" preference. This pointer may still pointing at the app on that old drive.