I bought the autograph with pictures 50th gold book last Oct. one side (the left) has a maybe 4x6 plastic/clear slot landsape size (horizontal) so if you take a vertical picture - it does slide in, and I bought some acid free tape for our scrapebook and taped the back of the pics - next to their autographs...
There are not that many pages tho - which was fine, DD kept the gold one for her Princess autographs, and we had last years book the regular blue one, smaller, for all the other characters we met!!
(if I could find it I'd count how many picture/autographs you get!)
For pin trading...I got dd some pins on ebay to start with, but the whole thing confused me... I had a fixed price I think of $3 per pin, and bid the lots... be careful not to bid on out of country... some lots are all the same kind of pin... and some pins are plastic... so I read the pin trading forum, and watched a few auctions, then bid...
Now your ages of your kids, it is your descion, sometimes dd just loved the pins I got her on ebay, and so she didnt trade them - which is fine!! Once a dad and his two young kids approached my mom and wanted to pin trade with her - he was embarrassed when I told him that its easier to trade with CM's they cant say "no" but my mom is attatched to a couple of her pins!! (He thought she WAS a cm!!

)
So it did distract dd at some of the stores we snuck into for the a/c to look at each CM's lanyard instead of begging for something!!