Wordpress Error

General information for the website: wp blog
Kind of development: Customization of existing website
Description of requirements/features: My wordpress blog site has an error which is not allowing for ANY changes to be made in the backend. this is because the 150mb max allowance has been reached on my hosting plan. 123 reg have said the error on the site is because of reaching the 150mb limit and have recommended to upgrade or delete posts/pages/content to free up some space.. the problem is it is not possible to delete anything because of the error.

UPDATE, 29/05/14

The website has been transferred to new hosting (myhosting) to alleviate the problem described in the original post. However, the layout of the website on the new website does not mirror the original (there are two versions of the website live, one on the old hosting and one on the new).

Please let me know if you'd like to have a look or think you can help.

Thanks
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