You asked for it - Here's my thoughts:
(For 2 ADULTS from the Northern VA suburbs of DC)
FLYING
Roundtrip airfare
cost = $250 per person, including taxes and fees
Room near airport night before early flight
cost = $130
Cheapest airport parking for 1 week
cost = $80
TSA security checks (take shoes off/empty pockets/put 3-2-1 bag in bin/dont lose boarding pass/put carry-on on moving belt/put shoes, personal item and camera in bin/walk through metal detector/walk back to bins and put in watch after alarm goes off/walk back through metal detector/locate bins/put items back in pockets/get one shoe on/tell TSA agent that yes, we can walk over to a table so he can examine the contents of my carry-on/pick personal item and camera/dont lose boarding pass/put on other shoe/pick up carry-on/follow TSA agent/go back to bins and retrieve watch/walk back to TSA agent and wait while carry-on is examined/finally get cleared to walk to gate/do head-smack at gate because 3-2-1 bag was left in bin at security
cost = my sense of humor
Waiting in a long line to board the plane while people that got on first sort out their carry-ons and block the aisle and then argue with the flight attendant when their carry-on is too large for the overhead bin
cost = 1 ton of patience
Finding out someone seated in the back of the plane put their carry-on in the bin over my seat
cost = my last nerve
DRIVING
4 tanks of gas at $65 to fill up each time
cost = $520 roundtrip
Expensive and unhealthy snacks from gas station stops @ $10 per person per stop x 4
cost = $120
Trying to stay with traffic and make good time for 13 hours while 1) getting out from behind slow moving trucks, 2) avoiding people who ride on my back bumper and 3) looking out for local cops with speed traps that will ticket for exceeding the speed limit by 1 MPH
cost = my sanity
Throwing in the towel and getting a hotel room in SC or GA for the night, round trip
cost = $260 (but get rebate on some sanity)
Hitting Orlando on I-4 at rush hour, even when used to DC rush hour traffic
cost = soap to wash my curse words out of my passengers ears
TRAIN
Train fare (bedroom w/bath), car fare and taxes roundtrip
cost = $1,230
Dinner
cost = FREE
Lounge car entertainement
cost = FREE
Ability to get up and walk around
cost = REBATE - Less Tylenol for bad knee and no sore rear end from sitting in one place for hours on end
Arriving in Sanford/Lorton rested after sleeping on the train
cost = REBATE - more alert for Orlando traffic/more energy for parks or home
Not having to worry about I-95 traffic
cost = REBATE - saved patience
Packing whatever we want however we want as long as it fits in the car
cost = nothing/priceless