I know I had some issues with something similar. I ended up checking ownership and permissions again and again until I knew it was right. Then I deleted out the config file (and on a few attempts the database) and tried again. I think I finally got it to go through on the third or fourth attempt. I think I found that when I let Moodle install create the database it worked better than creating it prior to running the installer. Also, double make sure that your moodledata (probably your "content") folder is correctly located and with correct permissions and ownership. I think I might have set everything to 777 just to install and then tightened back down a little afterwards.
If that doesn't work, redownload the Moodle files and keep trying. I was installing on a server that I did not have full control over and it was a little tricky but I did get it go eventually. (There was much cussing involved!)