Thank you all for your replies. I never considered about the laminate actually so I may well either recarpet or get large rugs in every room.
I have 4 kids aged between 2 and 10, I may well leave it another year if I do decide on a St Bernard so they are that bit older.
I have been looking into raw food, one of my friends has started her dog on this and highly recommends it but I am going to ask the vet about the diet in this breed of dog.
I don't drive I much prefer to walk everywhere, my vet, fields, a canal and woods are all within about a 15 minute walk so I wouldn't need one (I don't think).
It would be a bitch I would be looking to get but I would be getting her spayed so I won't have to deal with the bleeding.
I didn't think they were particularly territorial dogs so this has slightly worried me, I shall definatly look more into that.
The drool doesn't really bother me too much, I am going to get leather couches and wipeable wallpaper and replace anything else I can to make it as easy clean as possible.
I didn't know it was rare to get a dog without a congenital illness, I have read that you should get a 2 generation health screening report, but this is something I shall look into carefully.
There only seems to be one breeder in my area (the person I called) so I think my best bet may well be to talk to the vet before I make any choices.
I know its an odd choice but I have been in love with this breed forever and it feels like a good time to be making the choice. I really am looking into it very carefully and taking everyones points on board and if I have even 1% of doubt that it wouldn't be the right choice then I wouldn't get a St Bernard.
Once again thank you all for replying it seems there is a lot I don't know or haven't considered yet.