I don't protect a user from their own behaviour - like pressing alt-tab in a middle of a game without first pausing it or finishing the level.
I've only had this issue when the size of my game is out of sync with the size of the monitor it's displayed on - but switching to the ultimate fullscreen extension fixed it for me. I've never noticed an issue jumping between frames.
I have never used the windows control extension with ultimate fullscreen - I use either / or.
I start the game in window mode and switch to full screen - never the other way round.
Switching from the game to full screen / window on an XP machine requires a restart to display correctly on my test machine - which has many other issues (but users have reported back to me that my games worked fine on their XP machines). Alt-tab in that environment would be a mess either way (the machine only has 504mb ram).
You could create a test .mfa and post it and ask people to test alt-tab and see how many people have an issue with the taskbar to determine if it's specific to your machine or not.