Stupid Question: Firefox Bookmarks/Help

Scenario: I currently use a desktop as specced below (XP) and I am soon buying a MBP. I have hundreds, possibly thousands of bookmarks, many of which are Mac specific, like programs or widgets or anything else I found that I am going to download and use on my new laptop.

Stupid Question: What is the best way of moving all these bookmarks. It will be Firefox on both ends. Ideally I want to just export them to a USB drive, and then import them on the new MBP. Does this work. Similarly, I want to be able to carry my bookmarks across platforms, and to other computers, especially at college on my USB.