Well, here goes, since I have absolutely no idea if this is going to the right place.
A server would be nice, because then you could get the databases of a workstation that is being used. I am certainly not a fan of that.
As far as which one, you can't go wrong with a Dell T410 or above. As to what to put on it, that's a pretty loaded question as there are multiple options with how many drives, RAID or no RAID, which OS (SBS 2008 would be much strong choice). The best way to do it would be to just configure it online and get help from here or Dell.
As to the logging in from home, first I need you to answer one question. Why are you against LogMeIn. That is a turnkey solution that makes total sense and is free. Secondly, if you have a static IP address, which you should if you end up using a server and domain, you can use Remote Desktop, which can also be done with a dynamic IP only it isn't as easy.
If you did go with SBS, then you would have Remote Web Workplace, which is the absolute best way to log in remotely, probably even better than a straight VPN solution.
