Transition to Mac Mini

Question

Hi All
THE SITUATION
I have slowly been making the move from Windows based systems to Macs. I have a Small Business Server 2003 on a network with printers, a couple of laptops and a macbook pro attached to it.  Emails arrive at our server and then goto each persons laptop.  The server has been having problems and I have been dependent on third parties for support.  In part this was because the set up originally was made overly complicated with roaming profiles and complex security access.
We predominantly used MS Office including Outlook and I have MS Office for Macs 2011 on my Macbook Pro.
I am desperate to move to a simpler system that I have far greater control over and that I am a basic chance of carrying out more of the simpler changes, fixes, enhancements myself.
THE GOAL
I have just purchased a Mac Mini Server with Lion (omg i love Lion) and have been able to set it up very quickly with the view of using it as the new server, I chose the VPN option as that looks like it could be helpful later on but need to stick to baby steps at the moment.  The goal is to continue to work off laptops and the macbook pro until I can replace the other laptops with macs.
I have airport extreme base station and an airport express unit.  The great news was that my windows 7 laptop did not support my HP 3500 laser printer but I tried it on the mac and it now works fine - WOOHOO.
I have created shortcuts to the mac mini on my macbook pro and am ready to transfer files from my old server to the mac mini server knowing I can access them on the macbook pro however...
THE CHALLENGE
I have no idea how to:
1. set up my mac mini server so my emails go to it instead of the old server.
2. take my existing emails on my laptop or in the exchange server, and transfer them across into the macbook pro/mac mini server.  I need access to this information as my projects span a number of years and chronology of communication is an important element to my work.  Until I can make a clean migration I am stuck on using my old laptop for work as I email most documents to clients rather than print docs.
I apologise for the limited information but as a ludite trying to educate himself I am not sure how much or what information would be helpful.
Any advice on where to start would be really appreciated.

Answer 1

I just want to keep folks posted in case they have to do this one day. I am on my way to a working set-up.
1. Set-up DNS: I exported the settings from the old server and imported the settings on the new one. Worked great. i added an entry for the new server before i exported it.
- i pointed a laptop to the new server to test DNS resolution and all is working!
2. Set-up AFP: I got an external harddrive to put the home directories on. I set it up, and set up AFP to point to a folder and make it available to be a home directory
3. Set-up Mail: I configured mail how i wanted it based on my old server settings but changing it over for the new server name.
4. Exported the Users & Groups from Workgroup Manager. This is going to erase the passwords. i only had 25 users, so I could tell them their passwords again or ask them to email me it. Then for each record, I updated the url for the home directory, and the mail server. Because the UID's havent changed its looking good!
5. I unbinded a laptop with mobile user accounts from the existing working server and binding it with the new server. And voila! it is syncing as we speak!! Sending all the files down to the server no problem. I used a laptop that had an older portable home on it, as a test, but it is syncing perfectly and Kerberos is running great on the realm.
More to come as I work through this. Just want to document if there are others who can help or have this problem in the future.
If anyone has tips or advice, please post.