since you said you just got your N800 a few days ago, i would make sure you have the most up to date OS version before you try to install everything. i dont know if any of the N800's released now come with OS2008 out of the box but you probably need to update regardless. reason i'm mentioning it is because when i got my N810, i tried loading Skype and had the same problem as you (and i was already on OS2008 obviously). But then once i did a firmware update, it installed no problem. if i were you, that would be the first thing to try.