Can I use 1 modem for gaming and internet?

I have been playing my PS3 online for 2 years now through a wireless connection. I've decided I want to use a wired connection to hopefully reduce lag and enhance my online gaming experience. I have 1 router and 1 modem connected to it. I want to know if I hook my PS3 up to my modem, Will I still be able to use wifi on my laptop through the router and will I even be able to use my router at all?