Indeed, what you are seeing is not a graphics problem (Mate does not require 3D acceleration) but just how Mint chose to customize the desktop. Gnome 2 on Mint in the past also looked that way though it had a different menu. The screenshot is the default layout, like Ubuntu (and many other distros) have used when they still had Gnome 2.
You can change it yourself, add your own menu of choice (the old mintmenu is in the repository), add a top panel by right-clicking the panel, move applets to the top, ... Indeed, Mate is just as flexible as Gnome 2 used to be.
Registered Linux User #528502
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