I like Blogger, and their in-browser editor is pretty good. But I started blogging with Windows Live Writer last year and fell in love with it. There is an undocumented step you have to take to make it work with Blogger (or, more specifically, the Google XML-RPC service).
First you need to download Live Writer. Here’s the link: Live Writer download page
Next, you need to create an album in Picasa named “Windows Live Writer”. Log in to Picasa using the web interface and click on the “Upload” button. When the window for uploading photos pops up, click on “create a new album”. Name the album “Windows Live Writer” (without the quotes).
Finally, start Live Writer and configure it for your blog. It will ask you for the blog URL (mine is http://oldmaneric.blogspot.com) and your login information. It will detect your blog theme so when you add a new post it will look very similar to how it will actually look when it’s published. There is also a “Preview” tab that allows you to preview what the post will actually look like when it’s published. Uploading photos, resizing them, adjusting the layout, and so on are much easier with Live Writer than the Blogger interface. Give it a try, I think you will like it!