I've spent a lot of time making Remote Desktops function with OpenVZ containers and can get just about anything to run on it. The screenshots were too big so I uploaded a couple examples.
http://johnedel.me/2014/10/14/remote-desktop-on-openvz-container/
So far, I've run these:
- Ubuntu 14.04 w/ MATE Desktop (lightweight enough to handle just about everything you can throw at it
FileZilla, Skype, Firefox, Thunderbird, Nmap, GIMP, and probably things I can't remember that I installed. MATE is by far the most awesome of any XVNC I've used so far and hasn't crashed on me a single time since I built it about 5 or 6 months ago. I prefer running TightVNC in these environments. Requires no changes to /etc/inittab
- Ubu 12.04/14.04 KDE Full, KDE light, Gnome 2 and 3, kubuntu, ubuntu-desktop. Gnome is the most stable of any of these. PulseAudio crashes the session and it must be restarted or pulled. Weird keyboard mapping. Odd memory balancing but fine with VSwap. No changes to /etc/inittab
- CentOS 5/6, by far the simplest and quickest to install; ["sudo yum groupinstall "Desktop" "Fonts"] will pretty much get you going when you count dependencies. Only weirdness is sometimes Tigervnc-server doesn't install properly and figuring out the correct code in .vnc/xstartup takes a little while (gnome-session &) while commenting out 1/3 of this file.
- Fedora is garbage with this and I'll never touch it for a desktop again.
None of these ever exceeded 1.5gb at any time, and usually only held about 850mg regularly.
I once got Chromium working on a Debian + GNOME-Full on a container. It crashed after about 40 seconds. Might actually work with MATE.
I've not advertised here before, and I come from 13 years of WHT regulations and rules where I wouldn't be allowed to help you.
That being said, I'd like to extend an offer to provide a container and installation of any of these OS and desktop environments - that is, unless you'd prefer to roll it out yourself ... and with the specs you'd need not exceeding that of any 'industry standard' OpenVZ container, I'm sure we could cook up something sweet for you. At least see if it's what you were expecting.
Regardless of who you sign with, I'd suggest dual core power +1gb RAM +gb Vswap for minimal/lightweight desktops, or quad power +2gb physical + 2gb Vswap if you plan to have a lot of browser tabs, Skype, TBird/Iceweasel, GIMP, or want to use one of their jazzed up themes. I run X5650s and L5520s. The 5650s are all RAID 10, and the L5520s are RAID 1. Honestly, these things use more CPU and RAM than anything. I was surprised not to see the iowait I thought I would when I first started on these things, so unless a 'dd' output is a fate-sealer (generally around 90-100MB/s on the RAID 1 and 250MB/s on the RAID 10, but I'd take the extra CPU over the faster array.
I hope some of this information helps you and good luck!
-John