Forgive me if this topic doesn't exactly fit here, seeing as it's not technical nor operations, but I can't see any other forum it would fit in to. If only there was a GA forum

Anyway, I realize I'm probably going after a small number of people here, seeing as this refers to not only just Canada, but private pilots. I will try anyway.
I've logged many many hours (for a student, anyway), have completed all of my flight training except my last solo cross country, but have yet to get around to write the written exam. I ended up downloading a piece of software for practice, and while going through it, it asks quite a few questions I never even learned about in flight or in ground school. Questions such as things as ADF (it's the only one coming to mind at the moment).
I'm not really sure what I'm asking for here, but I guess I'm curious to know how complicated the exam actually is. I'm all for understanding everything I possibly need to know, but it's just such a vast amount of information that I'm afraid I might completely forget about certain topics.
The funny thing is (kind of pointless really), and I'm not sure if it's specific to my flight school, but you need to take a "written exam" with them and get a higher passing grade then with Transport Canada in order to take the actual written test. I say it's pointless because it's entirely possible that you could get 100% on the practice test, and 0% on the actual.
Has anyone recently (or ever, really) taken the written test and had problems with it? When I took the radio exam several months ago I studied as best as I could prior to taking it, but I completely blanked once it was in front of me.
I expect at least one person to criticize me, and that's fine. I'm sure at least one of you will think I shouldn't have a PPL if I even need to ask this.
Thanks to anyone else who can contribute though!