I believe you can add genre to the list of columns shown on the LHS of the screen. 'right click' and select from the list. This should then show the 1st genre of each film and allow you to sort by that.
(You just need to click on the heading to sort by that column)

(the proviso for this si that I'm at work so don't have dvd profiler here so can't check it out).

an alternative method is to use phpdvdprofiler installed on a server - either a free one or your own doamin name) and that gives full access to sorting by genre (since the link at the bottom of my posr).