Yeah you may as well go the full-cream milk, it couldn't hurt... and when you are able to eat more again, maybe cut back down to low fat milk.

Do you have a blender?
You can use milk, a scoop or 2 of ice-cream or frozen yoghurt, fruit such as chopped up banana/ strawberries/ mango, or a combination (I used to have banana & mango - yum!) and a spoon of honey... and thats pretty much it!
Very easy to make...

HTH