I upgraded to Windows 10 last week. Coincidentally got the Creative Cloud notification of an upgrade. Now I launch LR and ell works normally for a while. Usually after about 5 minutes - or a few edits - or prints (it seems to happen in all modules) LR just freezes ("Lightroom is not responding"). I close LR and re open and I am good to go for another few minutes. I am on Creative Cloud 2015.1.1 release.
Have you tried turning the GPU acceleration in the Lightroom preferences?
I tried that yesterday, Jim, but before I could ever un-check the "Use Graphics Processor" box LR would freeze on me. I tried again today - success. I have been using LR for 15 minutes and it is working great.