Please remember that you are not allowed to use your Dreamhost account for backups (anymore). So to make the storage of you pictures "legal" I would recommend adding them to a Gallery2 gallery.
As Atropos7 already mentioned, you can import the pictures which you've already uploaded - it works great, I do it all the time and my gallery has >11000 images in it already. Later you can even still access the original files as your Gallery2 stores all the original pictures in the g2data/albums directory, so it's still a backup.
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