OK, I'll try again with a quick summary and parts that I recall.
As mentioned, your Lacie HDD may not be dead, and you could try installing its drive into another known good enclosure.
As for your iPhoto and its libraries, and I'm guessing that you might be using SL 10.6.8 or??, but make sure you've only got one version that you're using and that it's up to date.
The messages you're getting may be correct, or your libraries could be corrupt.
A Google search on the errors you get should provide some solutions.
Basically, and I'm not sure if it works with all versions, but:
Rebuild iPhoto Library
Quit iPhoto if it is open.
Hold down the Command and Option keys on the keyboard.
Open iPhoto.
Keep the keys held down until you are prompted to rebuild the library.
A dialog will appear with rebuild options. Select all the options/checkboxes
Click Rebuild to begin the rebuild process. This may take a few minutes to complete.
You can use different iPhoto libraries by holding down the option key when opening iPhoto and select the one you want to use.
If that didn't worked then rebuild your iPhoto Library with this application,
iPhoto Library Manager (just try the trial version) :
Fat Cat Software
SL 10.6.8 version available here:
https://www.macupdate.com/app/mac/7158/iphoto-library-manager
EDIT: Opps, i see it says it's for "iPhoto v8.1.2, but maybe another version is available if you need it.
As for drives, I prefer to use Western Digital, but also use Buffalo and G-Drive external drives.
Now to post before I get timed out again. Good luck.