You could do a lot worse than an ex-racing Greyhound.
Yes, I know they're big dogs, but:
1. They are placid, affectionate and quiet and very good with sensible kids.
2. They don't eat very much for their size - only the dogs in race training need lots of fancy food.
3. They don't necessarily chase cats and small animals.
4. They need little more than 20 mins walk twice a day.
5. They need minimal grooming.
6. They usually walk very nicely on a lead (ie they don't pull you around).
On the down side, they're apt to be a little dim, are useless as guard dogs and love a nice settee to call their own, but they're so loveable you can forgive them for that.
Have a look here:
http://www.retiredgreyhounds.co.uk/
http://www.dogstrust.org.uk/information/factsh eets/otherfactsheets/
You'll need to register to see the Dogs Trust stuff, but it's free and probably worth doing in any case.