Amazon has a promotion going on right now, where if you buy 2 Disney movies from a certain list, you save an additional $10. We actually did this about 2 weeks ago, and spent less than $40 total for 2 Blu Ray/DVD combo packs. I even live in a state that gets charged tax on Amazon orders. The list of available movies is here. This promotion goes through the end of the month, and includes several movies that have just been released from the vault, or have just recently been released on blu ray, as well as newer movies like Chimpanzee.
The prices have changed a little since I ordered mine, but most of them are still right around $25 each, making the total about $40 if you don't get charged tax.
These could be great Christmas presents! It's hard to find Disney Blu Ray/DVD combo packs cheaper than about $20 each. We love the combo packs so we have the DVD for in the car on long car rides, and the Blu Ray for when we watch at home.