If you have a laptop, it might be worth while to take it along with you, and a card reader that supports your memory card. That way you can download your photos each night, view them on a large screen and delete the ones you dont like. It frees up space on your memory card, and saves you the hassle of doing it all once you get home. Also, when I have some downtime in the park, I scan through the photos and delete any that I dont want or are not good.
As for the cards themselves, it depends on what you will be doing with the photos. If you plan to print or enlarge them, then I would use the highest quality setting. This does chew up more space on the card though. If you will be emailing them, the smaller settings are better.
Check to see what the max size your camera will support. There are now huge memory cards out there, but many cameras wont support them. Also, it is better to have several smaller cards, vs one large one just in case the card becomes damaged. By having several cards, you wont lose all your photos! Thats another bonus to downloading your photos to a laptop each night. Ive also read of people going to a local CVS or possibly at WDW where they can pay to have the photos put on to a cd. That can be time consuming and expensive though.
Prices on cards have really come down, and check the Sunday flyers in the paper for even better deals. There are several types (memory stick, sd, cf, etc) so be sure to bring yours along with you so that you buy the right ones. As for brands, people have their opinions. You can do a search online to read reviews. I usually stick with the big name brands (Sony, etc), but then again, I am into photography and have a nice camera.
Hope this helps!
