Anyone got any ideas why WordPress wouldn't install on my site? Is it because it sees that I already have an index.html page in that directory and it won't install if the directory is already occupied?
I see a lot of horror stories on the WordPress support forums about problems that people encounter after installing WP in a subdirectory, so installing at root seems like the best idea--if I can get it to work.
It is most likely because it is seeing other content in your root directory. In general, there's no problem install WordPress to a subdirectory but sometimes people struggle with .htaccess rewrite rules or try to install it in a subdirectory and serve it from their site root which adds more complexity.
I've addressed your question about the installer in your newer post
so we can feel free to continue the conversation there