There is no issue with resolution on RDP. I gather it is limited to 1600x1200 but that's OK, and no client I have (laptop) will ever have a real desktop that size.
Sure there are other remote desktop apps e.g. Gotomypc, etc.
I run this over an IPSEC VPN so it is secure.
Citrix is where RDP comes from originally, but the server is complicated. One needs two computers to run the server end, though I gather one can run it on one PC running a VM. Too much hassle for this simple requirement.
I just wondered if anybody here is familiar with Remote Desktop and perhaps knows how to do this. It may well be in there, as a config file entry, etc.