Interesting question. I do wake up before I open my eyes. Many times, I don't even open my eyes for a long time after waking up as I prefer to sit in meditation then and there only.
But there are some people who sleep with their eye-lids open. So do you mean opening of eyes to mean opening of eye-lids? Because eyes could be closed even when their eye-lids are wide open. For me, opening of eyes mean when you can actually see using your eyes.
Philosophically speaking, waking up and opening of eyes carry the same meaning as awakening and enlightenment of soul. So yes, they can be said to occur simultaneously!
Hmm
The philosopher....
I think they happen at the same time too. And yes, I also know of folks that sleep with their eyes opened.
For me, I think if you must make a distinction, you wake up before you open your eyes