BLANK PAGE / BACKUP

I cant open my wp admin page, my website is now a blank page.

It all started when i upload a new theme. It keeps on showing my previous theme so i’ve decided to backup my database and delete some files of the old one. I think i’ve deleted something that makes my website and my wp admin blank page now.

I tried to restore my backup file using my phpmyadmin but it gives me an error message that the file is too big (480MB).

How can i restore everything? Would there be anyone there willing to help me with this concern? I’m just a newbie, and i really don’t have knowledge on this.

http://glow.com.sa/wp-admin/
http://glow.com.sa/

THANK YOU!