Decent watch, might watch again, and can recommend, but more for older audiences.
While "The Cat in the Hat" is a famous children's book, this is clearly just aimed at the folks that might have read it when they were children. That mixes the nostalgia factor with the slew of adult oriented jokes (like infomercials) and the unnecessary addition of mother being single and dating. Kids aren't going to find humor in those situations.
The material that is closer to the original book is much more charming and I imagine that kids will relate to it more as the kids are much more involved, or even the focus of the scenes.
The Cat in the Hat, even though he is the title character, is a support character to the two kids, played by Dakota Fanning and Spencer Breslin, who both do all they can with the writing to balance out Mike Myers as the Cat. I don't feel like Mike Myers understands the idea of being a supporting character: he gives me a very Tom Cruise / Jimmy Fallon vibe where if there was a pause, then would just center himself in the camera and do something to draw attention. "Oh yeah!" is a good example for this movie, a repeated, unnecessary line that doesn't once help the scene let alone the movie.
One would think after Jim Carey's "How the Grinch Stole Christmas" (2000) there would be a formula for how to adapt Dr. Seuss books (20 pages) to full length feature films, and someone clearly figured it out later in "The Lorax" (2012) and "The Grinch" (2018), so I'm....gonna blame Mike Myers.
Him aside, the movie has a lot of charm to it, and Alec Baldwin manages to work an unnecessary part to at least be a believable antagonist, though the best acting in the world can't make a bad part good.
If you're just really into Dr. Seuss, then give it a watch, but you're not going to miss anything special if you skip it.