We also just returned after driving from Minnesota, however, we made stops and didn't drive straight through.
For us, the drive went pretty smoothly but we did have a few issues. Number one problem was road construction in which everything backs up for miles, the Interstate goes down to one lane, and then once you get there nothing is going on. The cones are all set up, but no one was working on the weekends.
The other problem we had with driving was accidents. Last Saturday, we hit two major accidents that probably added 3 hours to our driving time. One of them was stop and go for miles. The worst part is when you get to the accident site you see the ambulances, helicopters and smashed cars. It makes you thankful that it wasn't you, but is still sombering.
Other than the unexpected things, the drive with our kids went very well. We have a TV/VCR in a bag that we took out the VCR and put in our son's Playstation II. Not only could they watch DVD movies on that, but they could also play video games.
To lisah1 - you are correct, Tapestry of Dreams is no longer running.
To cinmell - the crowds were unbelievably light in our opinion. I was worried about spring break and crowds but we had no problems. Part of the reason may have been that early in the week it was very cool (50s). But even near the end of the week I felt the crowds were light. For example, we rode Splash Mountain twice in a row, and then Big Thunder twice in a row, in under an hour, without fastpass. At 2:00 we got a fastpass for 4:00 for Pooh. In that amount of time we rode Space Mountain twice, TTA once, Buzz Lightyear once, Pirates once, had ice cream and still got back to Pooh by 4:00. To me that's very light for Magic Kingdom in the middle of the afternoon.