Paintings break...

Because paintings are entities, no blocks. Works as intended.

Paintings are Entities, not blocks. You can also destroy Minecarts and Boats.

Aren't carpets supposed to be entities to ?
Because I can't break them /w sword on creative

No, carpets are blocks. See block ID 171.

Got that. So I'm pretty sure signs are blocks to...because you can stack over?

For general questions about Minecraft, the wiki is your friend: http://www.minecraftwiki.net/wiki/Sign

Yeah thanks, forgot about that site...haven't played Minecraft about 2-3 months because I had some technical problems 🙂