IPHOTO Library file will not open after update of iPhoto 9.6.1

Question

I am trying to open up my IPHOTO Library in IPHOTO 9.6.1 with not success.
My computer is a Mac (27-inch, Mid 2011), 2.7 GHZ Intel core i5 processor, 8 GB ram, AMD Radeon HD 6770M 512 MB graphics card, 1TB Hard Drive.
My iPhoto 9..6.1 appears to be created on March 16, 2015 and was modified on March 20,2015 which I assume is from a security update 2015-003.
My iPhoto Library was created March 22, 2012 and was last updated March 1, 2015.  To the best of my knowledge, it has not been open since it was last updated.  Unfortunately there are no current backups to the file.
When I launch IPHOTO the screen shows a rotating sprocket then after a period of time I receive a message:
Your photo library is either in use be another application or has become unreadable. Shut down and restart your computer, and then open iPhoto again.  If the problem persists, try rebuilding your iPhoto library,  to do this , quit iPhoto, and then reopen it while keeping the Option and Command keys pressed.  You can also try restoring your photo library from a backup.
When I follow this am left with four  items to chooses from:  repair permissions, rebuild thumbnails, repair database, rebuild database.  The first is selected and assume this is by default. I am not sure what the best choice is to select.  Secondly since i have no backup of the file and I am not sure the file is corrupted, I started trying to create  a copy on on an external drive however the file (192GB Size) new completes a copy routine. I considered a backup process which would take multiple hours.
Looking for direction.

Answer 1

1. make a back up. No matter how long it takes.
Most Simple Back Up:
Drag the iPhoto Library from your Pictures Folder to another Disk. This will make a copy on that disk.
Slightly more complex: Use an app that will do incremental back ups. This is a very good way to work. The first time you run the back up the app will make a complete copy of the Library. Thereafter it will update the back up with the changes you have made. That makes subsequent back ups much faster. Many of these apps also have scheduling capabilities: So set it up and it will do the back up automatically.
Example of such apps: Chronosync - but there are many others. Search on MacUpdate or the App Store
2.
Option 1
Back Up and try rebuild the library: hold down the command and option (or alt) keys while launching iPhoto. Use the resulting dialogue to rebuild. Choose to Repair Database. If that doesn't help, then try again, this time using Rebuild Database.
If that fails:
Option 2
Download iPhoto Library Manager and use its rebuild function. (In early versions of Library Manager it's the File -> Rebuild command. In later versions it's under the Library menu.)
This will create an entirely new library. It will then copy (or try to) your photos and all the associated metadata and versions to this new Library, and arrange it as close as it can to what you had in the damaged Library. It does this based on information it finds in the iPhoto sharing mechanism - but that means that things not shared won't be there, so no slideshows, books or calendars, for instance - but it should get all your events, albums and keywords, faces and places back.
Because this process creates an entirely new library and leaves your old one untouched, it is non-destructive, and if you're not happy with the results you can simply return to your old one.  
Regards
TD