Gall stones are composed of mineral deposits which build up over time, and seems to be related to fats in the diet.
Gall stones present in the gall bladder often don't create problems until they find their way into the ducts through which bile should flow - they then block the way, and bile builds up causing pain, and local infection is also common because of the lack of bile flow.
Surgery nowadays is quite simple, involving a "keyhole" incision and use of telescopic instruments to breakup and remove the stones and / or gallbladder. Ultrasound (lithotripsy) breakup of the stones is another method sometimes used, but has a higher recurrence rate than surgery, and doesn't always work.
You can live without a gallbladder quite easily as it doesn't make the majority of bile the body uses to break down fats, but you have less ability to handle large amounts of fats at once in your diet as there is no big pile of bile waiting to be secreted.
I have never heard of vodka being useful in prevention of gallstones - maybe of kidney stones, as it's a fluid. Maybe a excessive intake of vodka limits your fat intake, though - too drunk to eat?
<edit> apparently naturopaths recommend vodka to prevent gallstones. Never heard a surgeon recommend it though

</edit>.
Hope all goes well for your dad, club, and I too would recommend a hospital where they perform these procedures often. practice makes perfect, they say.

Nothing worse that watching a surgeon who is operating and reading the instructions at the same time!
End physiology class.
Here's a good on-line info source:
http://www.niddk.nih.gov/health/dige...s/gallstns.htm
Cheers
Mick