We just want to dance to rock-and-roll all night long!

Another interesting way to say it would be something like "We just want to dance the night away, swinging [or bobbing, twisting, rocking, etc] to the (sound of) rock and roll". "dance the night away" means dancing all night long (you keep dancing like crazy, and by the time you stop and look around, you'll see the night has already passed [gone AWAY]). Here's a verse from an old song "Twisting The Night Away". Man, you ough to see her go Twisting to the rock and roll Here you find the young and old Twisting the night away