It's fine to repel mosquitoes from your body with DEET. However, the best solution to the mosquito problem is to stop them from breeding in the first place.
Most mosquitoes have a very short life cycle. The eggs hatch within 2 days. For 2 weeks, they are wriggling larvae. After a quick change, they spend a week to two weeks flying around as adults, laying more eggs. And then they're dead.
So mosquitoes spend half their life as harmless, helpless, wriggling larvae. If you prevent the mosquitoes from surviving this stage, you end up with exponentially fewer mosquitoes around your home.
Mosquito larvae develop in stagnant pools of water. This means you should be vigilant around your home. Empty out any -
* Dog / Cat dishes
* Bird baths that are not drip-fed
* Empty planters
* bottles / cans
* tires / car parts / tire swings
* wading pools
* buckets / barrels
Do an inventory of the area around your home. Anywhere that could hold water needs to be taken care of. If you are at all on speaking terms with your neighbors, be sure to talk with them as well. Remember, the mosquitoes that they breed will gladly fly into your yard to eat you for dinner!
Mosquitoes only tend to travel a mile or so from their 'home base' - and females stay even closer to where they can lay their eggs. So by taking strong steps to ensure mosquitoes cannot breed near you, you will make your time outdoors much more enjoyable.
Anti Mosquito Information
West Nile Virus Information