Extended warranty is just normal warranty extended.Accidental damage protection doesn't come with this laptop,it does come with some higher end ones so physical damage from user end won't be covered be it within warranty period or outside it.It's up to you if you want extended warranty.I didn't get it because I didn't feel about needing it.
If you don't use windows media player at all and don't need it then disable it.Click Start and under the search box type "Turn windows features on or off" and click it.
Under "Turn windows features on or off" find "Media Features",click it to expand it,uncheck "windows media player" which would also automatically uncheck windows media center.It would ask for a restart,restart and WMP would be disabled.You can enable windows media player if you want from there.
If you don't want to disable windows media player then follow this method:
In the start search box type "cmd" and click it.Type "regedit" in the cmd screen and hit enter.
Under the registry editor go to HKEY_LOCAL_MACHINE\SOFTWARE\MICROSOFT\MediaPlayer.
Hit "Installation Directory" key,rename it to something like "Installation Directory2".
Create a new string key(right click->New->String Value),rename it to "Installation Directory" and close registry editor.
It should get the job done.Fn+f9 would work as usual with other media players to play/pause the media,it won't launch Windows media player and neither can it launch any other media player.If you ever want to go back to default settings then just delete the newly created "Installation Directory" key and rename the original key(now "Installation Directory2") back to "Installation Directory".