One of the big weaknesses of having a Window's operating system was dealing with large files, specifically movies. In XP I never could get consistency and stability. From the editing to the writing of the DVD.
Having recently upgraded to Vista Ultimate, I had my first job where I needed to take some footage that I had captured and make it into a movie. Vista gets an A+.
I used all 'out of the box' software and was able to create a decent movie from the files I had. Then I burned it to five DVD's without a single failure. That is the biggest thing to me. Many times previously that was so unreliable that I'd resort to going to my old employer's and use their MAC!
First I took my AVI that I had captured previously, opened up Windows Movie Maker and made some edits to the file. With some title screen's, transitions and effects. Added a photo gallery at the end of the movie, then went to 'Publish' my movie. I needed to create some DVD's so next Windows DVD Maker popped up and gave me a few options (title screen or auto play, different themes in the title, etc..). Picked my options and 20 minutes later I had my movie on DVD.
Very nice surprise.