Myth tv is running great, nothing to complain about but one thing: The system time is always off! I did a ntpdate according to http://www.knoppmythwiki.org/index.php?page=TimeSynchronizeHowTo
I did this before bed, and when I work up the time was off again by around 4-5 minutes. Now, I was going to setup an ntpdate to run everyday or so, but when I type in crontab -e Nano returns nothing. What am I doing wrong?

Well since you didn't tell us anything about your hardware or what version of KM you're running this is just a stab in the dark. http://www.knoppmythwiki.org/index.php?page=Nforce2TimeDrift
Current versions should already have ntpd running "right out of the box", but if the drift is too severe that will give up trying and pack it in.