I considered this- they add up to 45 minutes so aren’t a movie on their own, but I think the main concern trying to make a movie from it is that Dooku doesn’t have much character in TCW beyond cartoon villainy. The most interesting Dooku stuff is probably the Nightsisters arc, though that’s not really a Dooku story, and perhaps Scipio, where he’s involved in fairly “Imperial” stuff but again he’s not a major focus. But probably best, you do have the Yoda arc going into Sifo-Dyas, which gives some good Dooku/Sidious stuff too, that could work.
Ah, I was thinking of the Sifo-Dyas arc myself! I think that might be it after all!