Gav's basically covered most of it!!
Myself and t'wife have recently done what you're thinking of and became 'parents' to an 8 week old labrador x viszla puppy and went from having very little dog experience (absolutely none in my case!) to properly thrown in at the deep end! She's now 8 months old and we've got a gorgeous, well behaved (mostly!) best mate for life. It is very hard work, but thoroughly worth it [bigsmile1]
We didn't want a small yappy dog either and my BIL has had viszlas in the past, so we knew the advantages (short haired, not massive hair shedders, not very 'doggy' smelling, VERY affectionate) and the disadvantages (very demanding, need a LOT of exercise/stimulation) and we stumbled upon the dog we now have by accident, but the labrador cross element does give her a brilliant temperament and the food obsession bit makes her easy to train. She's nowhere near as destructive as a collie for instance, but all our shoes are hidden in cupboards!!
My mate got a dog from a rescue place at the same time, some sort of mastiff cross, but no-ones quite sure, who was 5 months old at the time, already toilet trained, had basic puppy training etc. and he seems to have had an easier time of it. Not sure either myself or my wife could have coped with an 8 week old puppy on our own, so my recommendation is along the lines of your option 2).
Look at labrador crosses as others have said, they're less prone to pure lab hip problems and, depending on what they're crossed with, less likely to become a complete fatty and won't necessarily get that big. Ours is less than 18kg at the moment and will probably not get much above 20kg. I've also met a few people who have adopted retired greyhounds and they seem lovely, great temperament dogs.
Good luck, you won't regret it.
Oh and get RSPCA insurance!!

