response to No1. I would advise dell but im not with windows 7 100%. Windows xp is the most stable. Used by touch screens tills, large computer systems and most people in the home. more reliable too.
response to No2. With portables, i would go for the latitude too. Remote work may be a problem. Remote desktop sounds like the best, but you would need workstations constantly on, a static Ip address for your network then assign the workstations a specific workstation a port number so you could connect to a particular workstation. Also, if they are all going to be on a network, Depending on what your doing, do you need dual monitors?
Response to No3. I suggest a server and have all machines in a domain. IE, log on to any workstation and have a roaming profile meaning that your documents are in the server but appear on that machine in your my documents folder. Also, you could have Roaming workstations for the laptops, where they sync files via the internet. An internal email system that can be accessed from anywhere in the world with SSL for security. ( you would need a domain for this )Back up server with a configuration so automatic backups are done at 8pm everynight. UPS for all servers in the event of a power cut with software so the servers will shutdown if power isnt restored in time.
I would advise all files to be encrypted and sent to an offsite backup location. IE home or professional service. Backups not to a hard drive but a tape drive.
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