Soaring above the clouds

I am taking the girls on their first international trip tomorrow and I am quite nervous about the flight. I have taken Liana on a short plane ride to North Carolina, that was only about an hour or so, but this is going to be 6 hours and 2 kids. Hubby will be coming as well as my mom and my sis. We're actually flying out because it is my grandmother's 90th birthday and the whole family is meeting up to celebrate it with her. So now my extended family will be able to meet my hubby and my kids :)
Back to this whole flying with two kids thing, any experiences??? thoughts??? I am "hopefully" bringing a portable DVD player (hopefully because my sister is in charge of getting it out of a trunk that is complicated to get into) also packing toys to keep my daughters entertained..... but really how do you entertain a 7 1/2 month old??? She hates being on people's laps, she doesn't really sleep in her car seat (she has to be EXTREMELY TIRED) and all she really likes is to suck on her fingers but then she makes a huge pile of drool and it's just a mess! If i have the DVD player then Liana should be good most of the way with Barney and Dora over and over. If no DVD player, well I will have to think of a REALLY great plan b.
The sad thing is that when I asked people for advice about flying I was told that I should give my children tylenol or something to calm them?!??!?!?! I barely give my children tylenol unless they have a certified fever... no precautious Tylenol before the shots, nothing like that. I just don't think it's good idea- sorry to those of you who may do this. I was just raised very hollistically and I think it messes with the immune system when you use it without actual NEED.
So here I am freaking out typing away and I'm thinking what I should be doing is thinking of a plan B... ok. I'm off to finish packing and find the best PLAN B there is.... but then again, is there really one that fits this criteria???? OH BROTHER!!! WISH ME LUCK- see you when I return :)