I have many many old homepage photo and picture albums also, and when I tried to update or add to them, nothing worked.
So Ive sort of abandoned them, no thats not a good way of saying this, I still have them and all my friends and relatives still have the links.
But they will always remain the same.
Ive some nice photos which I do not want to have go poof and go away, and some pictures of the grandkids when they were much younger.
So my advice is to leave them alone, as you will ruin them if you try to update or do anything to them.
So our only way to do this is to use the new software to make new albums and sites, but link back to them.
I hope this is what you mean, as its been frustrating for me too.
I know I could access them from my husband's old Mac, but havent bothered with doing that. As I know it would just be a pain in the neck.
I gave up and just left them the way they are.
Jane
I forgot to add, that you can go back and get those photos, copy them to your new iPhoto albums and make new sites from them using iWeb or whatever.
Ive not bothered with this either.