Which are better family dogs, Weims or Vizslas? Which are better with cats?

No breed of dog is naturally good with cats. You have to teach them respect. Both these breeds are hunting, pointing dogs and both will need to be taught to leave the cats alone very firmly.

Weims and Vizslas have very little in common except they are both pointing breeds & admin is quite correct regarding the cats.
Vizslas are extremley loving and gentle in the right hands but they require firm kind training there is nothing worse than a vizsla that rules the roost! weims are more head strong than most vizslas but please do some more research ,visit some breeders of both breeds and form a informed opinion ,both breeds are gundog breeds and require knowledge and skill full handling.