Probelm with widgets & Display Widgets 2.03, fatal error memory exhausted

Hi all,
Apologies I’m not a tech savy person.
Two days ago display widgets stopped working, there are no checkboxes anymore and i get this error where they should be. Fatal error: Fatal error: Allowed memory size of 50331648 bytes exhausted (tried to allocate 787042 bytes) in /home/travelst/public_html/wp-includes/functions.php on line 336
Google translator stoped working also and i cant save any new widgets, i always get a similar error message to the one above.
I tried deactivating and deleting and reinstalling plugins but still no joy. I called my hosting company as i read in other posts to get your bandwidth widened, but i didn’t want to go near code myself. They said they widened it to 48m for working memory but want me to pay an extra 125 euros to widen it any more. I’ve only got two videos and 4 menus in widget area. I’ve got about seven plugins. I’ve around one hundred pages a lot with jpegs on them. Overall my site takes up 320mb of diskspace. Could it be i’m using too much working memory and need to upgrade??
Any help would be really appreciated as i’ve been building this site and learning wordpress myself and hoped to go live today!!
cheers, jimmy