Store 2 kgs milk powder
Store 4 kgs milk powder and 5 kgs lentils
Check the use by dates on the powdered milk you have stored. Make sure you are able to use it up because when it goes off, it doesn't smell very nice, and certainly won't be pleasant in your tummy!
Here are some ideas for using it up: http://denleydiaries.blogspot.com/2009/03/what-to-do-with-powdered-milk.html
It is your choice as to which lentils you store. There are many different varieties and they come dry or canned. I love canned as I don't have to worry about pre-soaking them. You can rinse them under the tap and they're good to go straight away. I have some dried lentils as well, but my family doesn't eat them very often.
If you don't want to store lentils, how about something like barley, rye or oats?