You're right, there are so many Web 2.0 tools that it is difficult to choose!
I explored My Heritage in the geneology category because I would like to know more information about my great-great grandfather. My Heritage has a powerful search engine for doing ancestor research that they say is constantly updated, a Family Tree Builder that makes it easy to add photos and anecdotes, plus family web sites where you can share information with your relatives.
The foundation of all this is the Family Tree Builder, which is downloadable. With this I ran into a brick wall because it is for Windows computers and I have a Mac. Bummer! Perhaps I can still use their search engine to research my great-great grandfather. But I’ll have to figure out something else if I decide to make a family tree.
I also looked into the start page igoogle and I plan to put that on my computer at home (the school homepage is automatically the start page on school computers here). I can tailor my home start page to show my interests each time I open my browser.