I noticed in another post you said you couldn't change the orders of songs in a playlist. This drove me crazy one evening, and took me hours to figure out, so I share your pain. It's simple, but at the same time, it's not.
Within the playlist, click on the little title bar above the track numbers. In my version of iTunes, it turns blue and there's a little up or down arrow when that column is selected. Then you can drag and drop to re-order songs. For some reason, if you've got Artist or Album or any of the other columns selected, it won't let you drag and drop to change song order.