I’ve had the same issue once so far. I reloaded the image from scratch as it was the most clear cut solution.
In future make a backup images of your SD card. You can do this by using the “Read” function on Win32 Disk Imager. (The tool you probably used to write the image to your SD card with.)
That way if things go wrong or you make a mistake, you can just revert to a previous backup.
As for the cause of the freeze at the splash screen, I can’t help you there. Help seems to be scarce on this forum, so don’t get your hopes up.
I’m still trying to figure out how to get eduke32 and prboom to work on my 256MB Pi. Haven’t had any luck or help so far.
Good luck, and hope this helps you a little at least.