UPDATE.....
I am now in my corporate office running the same setup described earlier with a few exceptions:
1) using two dell flatscreens (no Sony).
2) using a G5 Mac (not a mini)
3) using an IOGEAR MINIVIEW DVI 4 PORT USB KVMP Switch w/ supplied cables and power supply
4) Not using wireless keboards (all inputs connected directly to their respective PC)

I suspect the problem is with the $67 KVM switch at home. I'll drop $200 for the IOGEAR and hope for the best. Think I'll sell my wireless mac inputs as well to help soften the blow and free up some desk space for my next device.

Cheers!
-P