I suggest using the wiki, it's crazy useful for learning how to make stuff.
http://ringofbrodgar.com/wiki/Category:ContainersBut yeah go for cupboards, they're indoor only (they'll decay outside). Requires yeomanry, carpentry and knowledge of planks. By far the easiest storage to make for the storage space and size of it.
Crates and straw baskets are easiest outside until you can make coffers.
Or linen crates I guess.