
Most popular mainly means most well known and available. there are many rare or little known breeds that may be the ideal match for you. I found my perfect match in a very long established breed (been in UK since 1870's) that I had never ever heard of or seen, and I had always been a dog lover since childhood.
You eill have the ideal opportunity with Crufts coming up at the NEC in Birmingham (10th to 13 March) to see examples of all the Kennel Club recognised breeds, with breed lovers on hand to tell you the good and bad points of their breed.
When you hae chosen your breed make sure you only go to a reputable breeder (these rarely hae puppies available off the shelf) and be prepared to wait for the right pup. the best place to get details of reputable breeders are the breed clubs.