We are a welcoming community. Don't feel "thtupid" because you are lost. We are a massive clock with a bazillion gears.
Drop into IRC, and your questions will be answered more specifically, and quickly.
f6 gives you ff rw skip forward, skip backwards
f7 brings up the main menu
f8 gives you volume up/down lighting up/down in the given Entertainment Area (EA).
All of those WANT mouse input.
Right/Left arrow will give you skip given you are watching media which has skip (like tv).
MythTV has its own special set of commands, and is designed to not allow mouse... which sucks... but for kb check their wiki.
Those are the majors... again... feel free to drop into irc.freenode.net channel #linuxmce for "How do I..." questions.