RE: Batteries
You'll get 6v 700 MaH out of the 5 cells. But I would make one comment if you don't mind. Get batteries with solder tabs on them. Batteries like you show that don't have solder tabs can be difficult to solder too. If you get the end of the battery too hot the seals in the batteries will melt and the battery is ruined. The problem is that those seals don't take too much heat before they melt. And a battery without a solder tab does take a fair amount of heat to get a good solder joint. But with a solder tab you can make a good solder joint without getting any heat on the seals.
Hope this helps
Ken