HI
Trust hubby and kids to exit, very naughty LOL!!!
Seriously, don't worry about it too much as we have all, I am sure had similar embarrasing incidents with our canine pals

;)
It can be difficult to react quickly enough, but try to always be aware of your Douglas' body language and yo may be able to reel him in in time. Make sure he normally has plenty of interraction wiht other dogs or he may see them as terribly exciting if he isnt used to meeting them....
HOw about getting him to either look at you, or say, Sit, before allowing him to say hallo? If youreally persevere he will start to do this automatically. If he gets too OTT and jumps up then get him away, wait til he is calmer then let him say hallo again - you can use the saying hallo as the actual reward if he is well behaved, hope thaat makes a bit of sense.
Have fun :)
Lindsay