DV is about 12 gigs per hour of tape so be ready for that as people have said. Hopefully your machine is decently powered. Windows movie maker is pretty good and its wont cost you anything and is already installed. It gets panned a lot but I think its better than I-movie which everyone raves about for some reason. All the things you mentioned you want to do are in there. If you want to get more fancy like embedding multiple videos into the frame then that's when you need something more.
I used this book when I was starting out and it was very helpful to me. Its only a few cents too!
http://www.amazon.com/TechTVs-Guide-Creating-Digital-TechTV/dp/0789726564/ref=sr_1_13?ie=UTF8&s=books&qid=1217886372&sr=1-13
For uploading etc. you will probably want to render it a few different ways. You probably will want to render your final edited video into a DV file and transfer it back to a tape for storage.
You probably want to save it as an mpeg2 to make a DVD with it.
You will also want some sort of small file size version for the web, I would use youtube to host it. I think they take just about any file type so if you are using windows movie maker you might as well just render it as a WMV file, there are options in the program that will allow you to play with the final file size. You will want to do some trial and error with this to get a feel for what you think is the best.
Youtube is where its most likely to be discovered by people looking for what you have to show. Posting it to flickr or somewhere else will be ok for your friends that you tell but its not very useful as a social tool. On youtube you are more likely to make new friends and contacts that share your interests.
Some basic video editing tips:
Save your tapes! I wish I would have done this. Back when I first got a DV camera I used to just reuse the tapes after I had finished a project, now all my original full quality footage is gone forever and all I have are a bunch of poorly edited low quality movies. DV Tapes are cheap and small, label them and store your original footage, you never know when you might want to revisit it.
Don't go crazy with wipes and transitions, generally just use a standard fade and hard cuts
Keep the clips short, 10 or so seconds between clips is the maximum, several very fast cuts from different angles in a particularly technical section of the course will make you look like a pro.
Keep the overall length short 3-5 minutes should be plenty of time to tell your story. Remember, the audience wasn't there to feel the speed and g-forces so their attention span is very limited, show them the exciting parts!