For a lot of the topics mentioned (topology, differential geometry, nonlinear dynamics, etc), basically anything where there is a continuum instead of just finite structures, it will be difficult to make much progress without a solid grounding in real analysis. There's a great set of video lectures by Francis Su from Harvey Mudd where I did my undergrad,
http://beta.learnstream.org/course/6/
(or http:/and click through to the other videos)
Cool beans
Been looking for an easy i.e. video intro to real analysis. I tried to read Mandelbrot's Fractal book and Kip Thorne's gravitation books a while back and both of them quickly lost me since right off the bat they both go into metric spaces
I can also brush up on monoids too now