a couple other things to decide....
If your doing 2 and it sounds like you are, pick a color scheme for each girl album wise. I found it easier to keep track of whose albums are whose by assigning each of my children a color...ie...My oldest is pink, my middle daughter wanted black, my son is navy. The next choice is type of album, top loading, Creative Memories, spiral bound, 3 ring etc..there are loads to chose from. I personally bounce between Creative Memories and different types of top loading albums. CM albums are beautiful but do not allow for mistakes. If you put something in out of order you are pretty commited to leaving it there. With top loading albums you can pull your page out and move it where you want, because the page protector is what is in place not the page.
When it comes to pictures its not that you cannot use originals (i do) its just make sure you won't want a copy for some one else before you put it in the album. Then find a file folder and seperate each childs pics, label what/where/when, place any memoribilia (sp?) in the file too. Some events you will want in both books, some you won't.
Glue??? I use Creative Memories tape runners, acid free glue sticks (not often) hermafix dots, and Duck tape runners approved by Creating Keepsakes Mag. Be careful about glue being acid free/lignin free.
I prefer albums with page protectors. This way my work is kept nice and neat no matter how many times the book gets passed around.
Getting organized is the hardest part, cropping is the fun part.