(Newbie) My home movies are classed as Hollywood Movies!

I've just set up Plex Server on a mac with its own iTunes library, so nothing complex. Films I have ripped and imported into iTunes invariably get classified as Home Movies - which I know is iTunes' fault. But I also have hundreds of proper home movies imported from my Canon video camera/iPhone etc. Plex displays most of the as Movies! EG an 18 second clip of our family on the beach at Naples FL, shows up as some movie with Ben Stiller! Pretty much all my home movies have been badged up as actual movies - what am i doing wrong and how can i fix it?
Also, Playlists don't show up as they do in iTunes - so, Recently Added returns a "nothing to see here" message. Shall I delete the whole Plex stuff and start again, or is there a way to get Plex to actually read my library properly? Cheers and thanks!