Keep the fridge at a cool 1 - 5 degrees and chilled food will stay fresh for longer. Our most perishable (and often most expensive) food is kept in the fridge, so keep tabs on their use-by dates - the freezer may be the option for food we won't get round to eating in time.
Threw away the drawers that came in the bottom of my fridge and replaced with long thin plastic salable boxes now my salad ingredients stay fresher for days longer.
Using up Melons
Melon can be a great addition to your breakfast in the morning or as an afternoon or evening snack. Simply chop the melon into pieces and place them in an airtight container in the fridge. They should last up to 5 days.
Keeping Spinach/silver beet fresh
If you wash spinach and silverbeet well in cold water, shake off as much water as you can and store in an airtight container in the fridge, it will keep fresh for longer. This method also revives old spinach.
Bag it to preserve it
Green Bags are absolutely wonderful for keeping fruit and veg fresher for longer. Broccoli especially lasts far longer than usual - if you used to throw out a lot of broccoli when it started turning brown, this is one solution for you.
When I need to cool cooked food quickly, I put it on top of frozen freezer blocks like the ones for picnics, this cools the food quickly so it's less likely to get bugs in and can go into the freezer twice as quickly as just waiting to cool down.
Stop veggie going mouldy
Wrap lettuce, carrots, courgettes etc in kitchen paper then put them in plastic bags in the salad compartment of the fridge. They keep fresh for ages. The paper stops the condensation from softening the veg and stops mould.