Initial Character Creation Question

[porkchpexprs]

Hi. I'm new to Munchkin and really think I'll get into the game, but I do still have questions after playing my first couple games. For starters, the rules sheet says that during everyone's opportunity to create their starting characters, before the first turn of the game is actually taken, that players can put down races, classes, and "usable items." It's the "usable" part that leaves me unclear. Are you not allowed to put down items that you can't use because of class or race restrictions? Can you put down one-shot items? And, what about cards like "Really Impressive Title?" Technically, that's not even an item.