Need Help ASAP–Blog and WordPress Blank

I updated my wordpress version via fantastico 2 days ago and I thought everything completed fine. When I woke up the next morning my blog and wordpress admin are all completely white with text and images just floating around. I cannot do anything on my website, nor in the admin. I’ve contacted my hosting company and they can’t help me. Is this due to the upgrade? Is there a way to delete wordpress from my website and then try again to install it?

PLEASE HELP! I am a product reviewer and need my blog for my business.