[SoSpacey]

I have a similar, yet more complicated set-up than you so I think I can lend a hand here.

1- Use a standard splitter before going to each source.
2- Do NOT use your surge protector. You degrade your picture quality and it probably wont really protect you against a surge anyway.
3- I have all of my stuff in the same media closet. No worries, no damage.
4- Your wireless router will have ~4 wired ports. Use them. Wireless is great but since you have such a short run, hard wire the PS3 and anything else you can. The more you can hard wire the better.

IF you set up your splitter and you are experiencing signal loss, buy an amplified splitter. Your cable company may even provide one at NO COST. Cablevision does. They gave me a 4 way amplified splitter after I brought the main in to my basement.

Again, dont bother with wireless for the devices on the same rack if you can go wired.