This is the first report in four years I've seen of MSE malfunctioning like that, although the OOBE error does show up in logs as a minor error with a known remedy of deleting the oobe file in Program Data.
I suggest that something about your system is conflicting, so until time to reinstall I would run the other freeware recommended most here which is Avast. This solved other minor issues with one or the other in the past. This sounds more serious however.
Is this the original corrupt factory preinstall on the Dell? I would strongly consider doing what most tech enthusiasts do to Clean Reinstall - Factory OEM Windows 7.
At the minimum I'd Clean Up Factory Bloatware.
Here are other Troubleshooting Steps for Windows 7