What to do during 20 hour ride?

I'm going from England to near Barcelona in Spain by car and i don't know what i can do in the car. I will be sat with my sister next to me who's tottaly annoying and always talks. I can try reading a book but i doubt i'll be able to focus with my mum, dad and my sister talking and the radio being on. I do have my phone but it will only keep me bussy for few hours until i go on a ferry, after that i have no signal, i can listen to music on it but as i said only for few hours because i won't be listening to the same songs over and over again. Also if anybody knows, will i be able to download movies to put into an iphone 4 instead of renting or buying them? So can you please give me advice?

What I always do is bring my Ipod and phone and listen to music and just rest

You could take a portable DVD player and some movies.

1) Work on a word search puzzle
2) Practice your drawing skills
3) Read some magazines that you will be interested enough to read every word to keep yourself busy (mines gossip girl, etc.)
4) Sleep
5) Bring some cards for you and your sis to play with
6) Bring a book full of scary stories to read and entertain not just you but your family as well.