Computer goes black during bootup

When I start my computer it goes through the BIOS and then I get the light blue Windows Welcome screen with the flowers.
It stays there for a moment and then the screen goes black and I can't get to the desktop.
It used to always go black for just a second or two after the Welcome screen but now it doesn't continue.

I've tried to disable everything in the msconfig.
I can do that because if I hold in the power button it lets me reboot it in Safe Mode.
If I boot it in Safe Mode there is no evidence of any problems.

Any ideas what might be happening?

Thanks

I was able to get in.
Doing Ctrl+Alt+Del at the black screen and enter explorer.exe made it ok.

Thanks