Basic questions regarding installation of Kolab

[Duffields]

None of the books I bought to study Linux have any mention of Kolab in them so 
I am pretty much starting from a point of total ignorance to install Kolab. 

I used to think that I knew something about computers but I am obviously 
beyond my depth.  There are some fundamental questions that are not referred 
to in what I have read and I am not able to mentally tie the things I have 
read to the installation of Kolab.

Sorry to be so dumb but could somebody point me to where I can get answers to 
such fundamental pre-installation questions as:

1. Is it necessary to install Ubuntu server (or any server) on the desktop 
computer that will be used both as a client and as the Kolab server, or is 
Kolab a complete server?

2. The business of setting up my own DNS and connecting it to my mail provider 
(ISP) is perplexing.  My router provides DNS service. I think I know what DNS 
is and I think that Kolab will be a domain in itself and all requests from 
all the LAN computers will be handled by the router but perhaps I am wrong.  
I see Kolab as a repository of data as well as a file controlling/locking 
device that controls access to the data stored on the Kolab server. 

Since I do not have a www domain, I assume that Kolab just requests mail from 
my ISP mail accounts and then makes it available to each client on the LAN.

I am assuming that each computer on my network is considered a domain by 
Kolab.   I guess I am a bit confused by the fact that it appears that there 
will be at least two Domain Name Servers on the LAN and I have trouble 
visualizing how it all fits together?   Maybe I should not bother trying to 
understand what is happening and just get on with the installation, what?  

If there is any source of such on-line information suitable for ignorant 
newbies, I would appreciate knowing where to look for it. 

Thank you Allan and Paul for your help so far.

Cheers
Mac
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