I had to take a day of rest yesterday after the purgatory thread. =)
And you are right about what constitutes mortal sin. I try to get to confession once a month, but I don't always make it. It is required that you do so only once a year if you haven't committed any mortal sins, but I like to go anyway because its like having a burden lifted from your shoulders.
For newly converted members, I have found that they often dread this sacrament because it can be nerve-wracking not knowing what to expect in the confessional. However, after done once or twice it really is something one comes to enjoy.