Q: What steps and stuff required to add 2cd monitor to iMac

Hi,

I have a 27' iMac with 2.4 GHz Intel Core - (I don't even know what all of that means - but thought ahead that someone may need to know that!!)

Anyway, I've recently relocated some equipment from my office at work to home.  One of the items being a 27' Dell monitor.  I would like to add the Dell as a second screen monitor to iMac - the Dell has several ports, I'm thinking the blue 15 is where on the Dell a connection would be established; if thats the case - where and with what do I connect on the Mac? There is one port of the iMac that looks suspiciously like it is the place - but I don't know for sure.  It is set to the left of the modem in-port (blue cable in the photo that still has the bar code tag attached).  Any help would be appreciated. 

Thanks everyone!!

Mike

This is on the Dell - but I don't think needed for today's purposes - inlcuded only so I didn't leave anything out in case there might have been additional questions about what else is there.

Next, below is the iMac - that little pin plug in - or whatever they are called - looks like computer hieroglyph for "plug a video monitor in here stupid" - but since I am not Indiana Jones - I'm looking to those with actual wisdom about such things.  If that's the crime scene, what is it called???

Dell - I'm thinking the blue 15 pin is the place to plug in  (right????)  (no???)

The follow up question, in case I didn't already make this very clear, what is the cable or adapter or whatever is needed actually called - so when I go to Apple or Best Buy or where-ever I don't have to then convince someone else how little I know what I'm talking about by reinventing this conversation for them too - which usually leads to them confusing me further once I have already made my mind up that I really know what I want/need and learned from the people (here) that I trust the most about such matters.  In other words - I don't want anyone to confuse me with the facts once I leave this conversation!!