Fatal error: Allowed memory size

Hi guys

I'm having an absolute nightmare trying to get the cart to work...,All I want is to be able to display the products for a small store in a "catalogue only" format. The client is selling furniture and has no need for anything at all apart from the ability to display products, a few images and a price. I have added the categories that I want to use, added a couple of products to the categories, and set up a link in the menu to link to a category list.

When I then try and click the menu link on the front end to look at the products, I get the following error:

Fatal error: Allowed memory size of 50331648 bytes exhausted (tried to allocate 122880 bytes) in /home/********/public_html/components/com_hikashop/views/category/tmpl/listing.php on line 102

I notice that other people are having similar issues and that they have been resolved by altering something to do with "characteristics" but I do not have any characteristics or other information entered...All I have are length, width and height specs, a price, a short description and some images. I created a php.ini file with the following information and uploaded it to the root folder of my Joomla installation:

register_globals = Off
upload_max_filesize = 50M
post_max_size = 30M
memory_limit = 250M
upload_tmp_dir = 100M
max_execution_time = 360

I am using:
Joomla! 2.5.6 Stable [ Ember ]
PHP version: 5.2.17
Apache web server
Database version 5.1.61-log

Site URL is: host.quksdns13.net/~pulpvint/

The client is getting very angry (following a disastrous attempt to use the ridiculously useless Virtuemart) and I would really appreciate it if somebody could please help me get this store working!

Many thanks in advance to anyone who can help.

S