I am not sure or am not understanding the user for server 2 in your scenario. I would just run AC on the first server. Plus, you can only have one SBS on an domain as the SBS server will have to have the FSMO. What I would do is build your first domain with everything on the server, then add the second server and either run Windows Server 2008 Standard or the Premium Add-on. The latter allowing SQL Server but really no difference. Not being SBS, it can be a second domain and also function as your TS/RDS server. TS is not used any more. Remote Desktop Services Server is the official name. Then clients both on the network and from home can log in and run their own sessions or see the whole desktop. These users will all need separate CALs.
RWW which in 2011 is now known as Remote Web Access can be used from home to access either computer. RWA is the most secure form of remote access and also gives other advantages once you access the site. However, most people just want access to their desktop or RDS and, therefore, choose RDC which is much faster to connect (maybe three to five seconds) rather than the 30 seconds it will usually take to open RWA and then connect, etc. I still like the Standard version, but mainly because I prefer Exchange and SharePoint to be onsite.
