I think you were too hasty. I'm a first year mathmo at Exeter College, and I sort of know how you feel(/felt), but I think you were dead wrong.
I suppose pressure on you might have been a factor, it seems a bit lax at my college. The linear algebra is difficult to understand until it is put into real terms, and your tutors are there to help you with problems if you are really stuck.
Strangely, I think the opposite way around, that the Analysis and the LinAl can be interesting at times, wheras the calc and dynamics are boring at all times (not sure about the probibility yet, it's ok).
I just can't imagine what would make you want to drop out, when all you had a problem with was two courses, one of which the lecturer said at the start of term might be tedious (analysis) and one of which my tutor said was fairly useless and not very interesting on it's own (LinAl). Plus, I'm not sure how much related material you have to take in further years.
:/ I guess I'm not you, so I can't really tell what it was like for you.
As for a gap year, try lots of new things. Ever wanted to be a musician? Try and bum a living as one.