dont do it, if you just want the movies then you can buy a media thing for the DS for like £20! it uses compact flash and there cheap for a huge amount of memory, they just sitback and download all the films you want of the net and watch them in bed, allthough i prefer to just play games. get mario ds, play the metroid demo, get wario ware, its funny and addictive. maybe think of getting rayman, its... well its kinda good actualy.
stick with DS, head over to
http://www.consoleplus.co.uk/index.php?cPath=32_66
for the media thing