The model of TV may have affect what sort of media files it can play, but the difference in the menus that the OP is seeing is because JRiver has a different menu system for the PC client and for DLNA equipment.
This statement is not necessarily true. The format of the browse tree depends on the Control Point (i.e. on the TV) manufacturer:
1) Some Control Points follow the browsing tree structure defined by the server (in this case MC); such Control Points use the UPnP "Browse" metaphor to display the various branches and leaves of the browse tree of MC's content directory.
2) Other Control Points have their own internally defined browsing tree structure; such Control Points use the UPnP "Search" metaphor to fetch entries from MC's content directory and to populate branches and leaves of the CP's own internally defined browsing tree.
However I don't know if your Sony (Bravia) or Panasonic TV uses the "Browse" or the "Search" metaphor.