What video card using?
if can access menu see if can get into 'window manager' or 'window manager tweaks'
if can't probally means 'xfwm' and/or 'xfdesktop' not running....need to activate those ang kill process of other wm's that may be running.(use task/system monitor/manager Then resave session, and make sure at logout box check box to save session NOT CHECKED
P.S. stay away from 'MintMenu' in Xfce it was designed for the Main Edition (Gnome) and the port to Xfce still has some glitches.