For the chat window... Open Window Options and set the dropdown to Frame and Title. Now use the opacity sliders to hide the title if you don't want to see it. What this does is set that one window to show the chat input the first time you mouse over it. Generally you'll do this to one chat window you use all the time to type in while leaving the others alone so they don't waste space.
As for the loot window... what lordebon said
