A lil' bit of maths:

You only have 2 sensible choices
1) Cab to Tsing Yi + Airport Ex Chris' about right. $90+30 and up to 45-50mins journey w/out terrible traffic

or 2) Cab it through: if google map is to be trusted, it's some 230 full price (free from traffic) and around 200 discounted. let's say you may or maynot get there quicker ( 15-20 mins from tsing yi, depending on how quick the driver goes)

However, if crap happens on Lung Cheung Road that day (although it seems to happen a lot less now that Route 3/5 have diverted some of the traffic) then u'd be quite tight in time.

But, I guess if you are really ambitious, you can try this: Kln tong/Prince Edward/Lai King/Tsing Yi/Tung Chung/Airport. (MTR says Kln Tong-Tung Chung is 36 mins, I'd pad in another 30-40 mins to be safe from HKBU and for the S1 ride)