What you want depends on the type of "blue plug" you are talking about.  
(VGA or DVI) Go to a place like newegg.com and search for "kvm switch."  
Or, better still,  go to your local computer hobby store, Best Buy, or 
Radio Shack and describe what you want to do - bring along the cable 
with the blue plug.

Solutions exist to your problem.  You plug in both computers to the 
switch and you can use the same keyboard, monitor, and mouse if you want 
to.  You press a button or turn a switch or something.  They don't cost 
a whole lot, as a rule.  Off-hand, maybe $25.

Dean Kukral

On 9/17/2010 9:33 AM, Diane wrote:
> *I was wondering if there is a way to hook up one monitor to two computers
> and use them at the same time?  *
> *
> *
> *And how would you switch from one computer to the other?*
> *
> *
> *I'm using Win7 on one computer, and XP on the other.  Regular blue plug on
> monitor, not usb.*
> *
> *
> *Thanks.*
> *
> *
> *Diane Kroeckel*
>
>
>    

              The NOSPIN Group is now offering Free PC Tech
                         support at our website:
                          http://freepctech.com