problems after moving host, displays page full of characters

I have recently purchased a online store. They would not give out installation files to install myself, rather i had to sign up for a minimum of 1 month and backup the entire site and then restore it on my other host. So, i backed it up (files and database)and performed a restore on my host only to run in to problems.

The site does not display properly and just has a page full of numbers and letters. I have no idea whats wrong, im only a newbie. Could some one please help?.

After it didnt work the first time i deleted everything and installed a fresh copy of wordpress, which worked fine, so then i uploaded the theme and relevant files and it all turned to crap again. So im guessing something is just wrong with the files in the theme?

The original website on the original host is working perfectly its only on the new host that i restored it onto that has a problem

The original website is located at https://www.nzinvasion.co.nz and i have moved it to my new host at dvd.weddingmagic.co.nz.

You can have a look at what i mean. Its a really nice website and i need it working if anybody can help me please
once i have it working i will purchase another domain name.