I sympathise. I'll try to answer as best as I can but someone else may be able to give a more complete or better reply.
Did you just download LibreOffice or install it? If installed: On the metro (tile interface) scroll across and see if a tile has been installed for LibreOffice. If not open the charms and in find apps type LibreOffice. Alternatively go to the desktop and you may find LibreOffice has installed a shortcut. If not installed then go to the desktop and click bottom left and look for downloads.
Have you registered Norton on the new system?
IMAP and POP are 2 different email protocols. If your account was set up for pop then stay with pop. Don't use Thunderbird so cannot help with transfer of address book.
This link tells you how to move the downloads folder but the first part is what you want is it tells you how to find it.
You may be younger than many who answer on this forum!