just mentioning that static isn't really necessary unless you have a lot of computers... 1-3 isn't going to be a problem 9/10 times.
That depends on the router, and sometimes on the version of the firmware in the router. Some routers will not forward ports to leased addresses (which makes sense unless the user is aware that he must always boot the computers in the same order). I can't give you a definitive list (I don't own every router), but Linksys and D-Link seem to have done this, at least with some firmware versions.
That's why the general rule of thumb on PortForward is to use static IPs for any computers that will have ports forwarded - it eliminates one possible problem and doesn't cause any.
