Yes, it can run VMS. I can't remember for sure if the last version of VMS for VAX still supported the uVAX II, but if it just have enough memory it should work fine.
It's an interesting system. Two ethernet ports, RQDX3 (disk controller) and TK50 (tape controller and drive). VCB01 is the graphics system. Only one VCB01, but there are two distribution panels, so I wonder if it actually served two users with graphics at some point. Don't think I've ever seen that, but I wonder if it might have been possible to run it like that.
VMS actually use X11, but commonly over DECnet.
The ports on the rear are the two ethernet AUI connectors, and two times display, keyboard and mouse. And then the serial console.