no hard drive space on Macbook, exporting iPhoto Library to external hard drive....?

[Stephanie]

I know there are a ton of discussions about this but none of the answers are very clear to me so I thought I'd just start my own. I have a Macbook Pro (Summer 09) with a 500gig capacity and I'm out of room. I have almost 100gigs of photos that I need to get rid of. So far, I have successfully dragged the Iphoto Library icon in my pictures folder to my external harddrive and it loaded. I opened another "User" on my macbook and opened the iPhoto library to confirm that it moved correctly. So I've got the hard drive figured out. Now I disconnected the hard drive and tried to reopen iPhoto and got that window about choosing a library and I created a new one which is empty (Which I assume will be the new one I will be using). This step lost me when I looked it up in other forums because I don't think anyone mentioned creating a new one but I also don't think what I did was wrong, so I guess my future photos will go into the second, new library.
So what do I do with the first one with all my photos in it still? I know they copied into my external hard drive fine but they are still in my internal hard drive too. How do I delete them so I have the room on my computer again? iPhoto confuses me so much sometimes... do I just drag the first iPhoto library into the trash? What about all those hidden albums (like when you right click a photo in iPhoto and click "Show in Finder")?
Also in the future when I want to use any of my pictures can I just plug in my external hard drive and open the Library again?
Thanks so much and any help is appreciated!

[Bob]

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Hey, I enjoyed your question, I have worked as a technician most of my life, I
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Good luck...

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