Fedora 19 problem

[Roger]

Hi all.
Last night Fedora 19 updated 189 files, akmod and kernel among them.
Now Fedora boot stops, I think because the kernel-devel file is faulty 
and nvidia cannot compile, or maybe partially compiled.
I have tried reverting to earlier kernels and down loading the devel for 
that but yum reports that everything is up to date and stops.
I see there's a lot of problems with Fedora 20 so have not tried 
updating that yet.
What's the best way to resolve this please and get Fedora 19 nvidia gui 
working again.

Thanks in advance
Roger.