here is a 9pin serial port switch box...
http://www.pchcables.com/ab4waydb9ser.htmlthat one will allow you to have up to 4 different console adapters hooked up at the same time to a single x-arcade. you just turn the knob to switch between them. ( used a 2 port version in my cabinet a long time ago to switch my x-arcade between my PC and my dreamcast.) i ordered from that site and was very happy with the product and customer service.
don't forget the 9pin cables as well (male to male i believe)
as for the video switch, this is a pretty common item. alot of people use them so they can connect multiple game consoles to a tv that doesnt have enough video/audio inputs. you would have to know what type of video cable connects your xbox to your TV to make sure you get the right one (component, s-video, or composite). you need to make sure you get the right kind.
depending on what other consoles you are connecting, and what inputs your TV has you may or may not need to do this. alot of TVs have multiple inputs on the back, so you could hook the xbox to one of them, and the playstation 2 to a different one, and just use the TV remote to switch between them. if you dont want to bother with that, or only have 1 set of inputs, then a video switch box would work. you plug the xbox and ps2 into the switch, and it connects to the TV, you then push a button to switch between the two.
something like this would work fine if you are using component video:
http://www.monoprice.com/products/product.asp?c_id=101&cp_id=10110&cs_id=1011007&p_id=3027&seq=1&format=2if you are using s-video or composite, then perhaps one of these...
http://www.walmart.com/ip/RCA-4-Way-AV-Switcher-With-S-Video/3312963some have remote controls, some dont. if you are going to use a switch box, you need to make sure you are using the same kind of cables on both consoles.
I am not doing this anymore, however like i said earlier, i have a ps2 and a pc in my showcase cabinet. i dont need switch the controls between the two systems, since i only use the ps2 for gun games, however i do use a video switch to change between the pc and ps2, which both connect to my tv via component video.