How do I recover my iPad data & sync it w/the new iOS 4?

I have all the things from the iPad on the laptop in iTunes. I did back up. What is happening is the iOS installs, but the apps will not restore to the iPad. That is when it freezes.

Good news! Sort of... My iPad finally completed it's reboot. I just left it for about an hour and a half. It was "stuck" at the 80% mark, but just came up. I was NOT connected to iTunes. HOWEVER, it's in the restore to factory settings mode. NONE of my apps are there. Oddly enough, though, a calendar event I had in it just beeped an alarm. I tried the photo app, and it took a while to "rebuild" the library, but after a few minutes, it restored some of my pictures, though not all of them, and all the event names are gone, replaced with a three digit number and IMPRT (looks like 102IMPRT). I'm not sure why some events were recovered/saved and others were not. I don't see a common, linking factor yet.

The question I'm asking myself is whether to try restoring from my back up or not.

Note: The iPad finally rebooted with iOS 4.2.1 installed. (See last post.)

Okay! I threw the dice & hooked the iPad up to the laptop with iTunes open. Unfortunately the reinstall of iTunes defaulted to the automatic sync, that can only be changed when the iPad is already hooked up. (I hate that.) In any case, the sync started before I even realized it, being used to it waiting for me to click the sync button. I was going to attempt to restore from my backup, but given all the trouble this has been I didn't want to interrupt the sync, so I let it go. I seem to have all my apps. My address book seems to have all its data, as do my calendar, Pages, Numbers, Keynote, Notetaker HD, Penultimate, ReaddleDocs, and PDFReader. Most of my books, and all of my purchased books were in iBooks, but 5-7 of the free books I'd downloaded from iTunesU were missing as were the three video lessons I'd downloaded from iTunesU.

Summing Up
1) I tried reinstalling the latest version of iTunes, but experienced the same problems as previously described.
2) It appears that the new iOS 4 finally rebooted after about 90 minutes or so, despite the apparently normal progress to the 80% or so mark, and then apparently freezing. WALK AWAY! Do something else & see if it reboots. This obviously takes LOTS of time! It was NOT hooked to iTunes. I don't know if this was key or not. iTunes kept freezing, so I did a Force Quit, and left it off.
3) When the iPad finally rebooted, all my apps were missing. I opened Photos, and it spent a few minutes rebuilding my photo libraries. I was missing some photos, but most of the albums appeared to be there. My calendar appeared intact with all dates, appointments, etc.
4) I opened iTunes and synced my iPad. I seem to have the majority of my data. I'm not perfectly happy with the percentage of recovery, but I can live with it.
5) Recommendations: a) If you're already experiencing what I was, try the steps above. It's exceedingly frustrating, but I finally got my iPad working with the vast majority of my data. b) If you haven't updated to iOS 4, DON'T!! At least not until Apple puts out a fix for this major iOS update problem.