I am looking for the title of an animated film from the 80's I thought the film was called gnomes but I can't find the right film under this. The plot had to do with a family of gnomes that lived under a tree root in the film there was a wedding but when the bride lifted her vail it was a trol and the bride had been kidnapped by the other trolls any ideas

Is this the one you're looking for? Gnomes (1980) (TV) (http://www.imdb.com/title/tt0343727/)
"A family of gnomes preparing for the wedding of their oldest son must engage in a battle of wits with an enemy family of vicious trolls."