I have checked the error log and also searched in google. I don't have a definitive solution, but only a few ideas of what could be the problem. I explain why I think this in every idea:
- Operative System: you say that you use Windows Vista x32, it seems Unity generally doesn't work well in this OS
- Hardware, more specifically RAM memory: in the error log I found these lines - 88% memory in use. 1916 MB physical memory [223 MB free]. This may indicate that for some reason, you are trying to run the games with very high graphics, too high for your PC setting. Try to run the games with the lowest graphics and check if it works.
- Antivirus: I read that antivirus can cause issues with launching
- Register: I read that some people had broken register and they did some fixes that solved the problem, you can try to use CCleaner to repair register and see if it works
I hope something is helpful, I'd say that the problem could most likely be the RAM, using 88% memory is insane, and if you only have 2GB of RAM, you should run these games in lowest graphic setting possible. Tell me if you could solve it!