Connecting the router into the switch is the way to go. The remaining user can be plugged into one of the router ports. Now you've got room to expand on the router or go with the wireless option.
I assume you are currently using windows ICS? Make sure you disable that after you get the router up and running.
I'm in an office that has an 8-port switch already setup and functioning. My boss would like to have a wireless connection. Now my options seem to be: find a 8-port wireless router(not likely), connect a wireless router to the switch (which is what I'm trying right now), or convert most of the computers in the office to wireless(probably what I'll end up doing).
I should mention that all ports on the switch are used. As well, I would need the computers that use the wireless to not only connect to the internet (that's easy, got that already), but to also connect to the computers in the Office LAN. (REALLY need this, there are programs in use that connect to each other for sharing information, this is vital)
I think it will be easier to get a 5-port wireless router and connect most of the computers through it, and convert the rest to wireless, but if I could get away with connecting the wireless router to the switch and still be able to connect to the other computers in the office, that would be great.