So let's say I want to transfer my pictures. If I move iPhoto to a external USB port,
I assume you mean Disk no port...
will I be able to open those pictures and movies on ANY computer
Depends.
You need to distinguish between the
Library and the Pics and Movies. The pics and movies are not changed in any way by iPhoto they will play no matter what.
The Library, however, will only be available to a Mac with the current version of iPhoto installed. iPhoto has no cross platform ability whatever - nor does it claim any - and the Library contains the various versions of the photos too, which tends to confuse other folks surfing with a File Browser. In that scenario, simply export the pics from iPhoto for use on the other machines. However, if this is a constant requirement... don't use iPhoto.
Can I back up without making all my pictures and videos STUCK in iPhoto?
File -> Export. But this will only back up your Files, not your Library - Albums, Books, Slideshows etc.
What if this iPhoto file becomes corrupt and just can't open up anymore. How do I extract me pictures and videos then?
It's not a File. As I said above, it's not a File, once more, it's not a File. You can always get to the Pics using the RIght-Click -> Show Package Contents trick. If, for some reason you can't do that, then you have bigger problems than iPhoto.
What is iPhoto Library? Is that the file disguised as a folder? Or is this something else?
In your Pictures Folder you'll see an icon called... iPhoto Library. That's it.
Logic Pro quits and truncates my projects ALL THE TIME. How do I know iPhoto won't freak out and lose a batch of my pictures too?
As I said above, that's why we have back ups, right?
If you read these forums you'll see lots of people posting that 'iPhoto has lost my Photos', but if you read the threads 99.9% of those cases resolve with no data lost whatever.
As of the .01%, well User Error can play a part too.
Regards
TD