Picking up my new Prius!!!

I need a bit of help. First I would like to thank everyone on the board for everything they have taught me about the Prius. I am better prepared than 90% of buyers thanks to all of you. It has been a journey from making a decision (is it time yet) to ordering to getting a car. I got the license and registration today. I get the car a week from today. I would like a bit of advice on the pick up and drive home . I have the pick up check list and have downloaded the manual and yes read it. So here are my questions I hope you can help.
First any tips for pick up. I am interested in stuff that is not on the list that most folks might forget. Check oil? Check air pressure? My son gets his car serviced at this dealer so I don't want to be too big a pain in the posterior but I also need to drive this car 700 miles and go to work on Monday.
I plan to drive around up to Wolf Creek "Buster wants to fish"(and by the way old Rawhide house is still there) and Craig and then back to Helena then around town to meet my son as he has to work that day. I would expect that to be 40-50 one way. Things are a bit far apart in Montana. My son drives to Great Falls to see movies, one hour at posted 75 mph though he probably goes 80. So I expect to put 100 miles the first day. My concern is the "burn off check engine light" thing. I have to be back home in Olympia on Monday at 0 dark thirty. I intend to ask the dealer about this but do I keep driving or stop or what.
Now we get the the drive home. Saturday, Helena to Missoula about a hour and half 70 mph on two lanes for 2/3 and 75 on I 90 for the rest. You go over the divide on the steep side just out of Helena. Reads steep grade up 2-3 runaway truck turnouts going down. Some fishing on the way. Over night at Missoula. Any suggestions particularly the climb? How fast to go. Remember this is Montana people drive 70 on two lane roads, speed limit is 75 on I 90 to the top of Lookout Pass. I will not sacrifice this new car to "go with the flow" however I do not want to be run over either. Suggestions?
OK here is the Montana gas thing. Regular unleaded 85, mid grade 88. I assume I get 88 right?
Moving on to the drive from Missoula to Olympia. Three passes and three areas with potential for really significant crosswinds. I would like driving tips for this.
Finally any tips for the "handling" the local dealer who has lost the sale and has to service my car.
I guess I am asking for your advice and council. I haven't had this much fun in a while!