A birthday party.. really important i need help!?

Okay so my invitees list is 14 people but i think thats too much considering we are gonna be sitting in one room in the basement so how many people do you think i should invite over? The room is a little bigger then an ordinary bedroom. Okay and im also confused on what time shall the party start and end and are sleep over partys fun or too much work? And one more last thing, okay so there is a nintendo wii that i really like and we can use, a tv, dome dvds, cards, uno (another type of cards thing), i donna board games like monopoly, wwe, sorry, and whatsoever. What else shall i do on a birthday party that will not cost me alot and no i odnt have a pool. Please answer some of my questions cus im not a party person! And no im not making a dance party!