Your homeowners insurance covers the home, other buildings on the property, and your personal property. Property is usually referred to in a home insurance policy as the "contents," and includes everything from your jewelry to your CD collection and the pictures hanging on your walls. Because your personal property is covered under the homeowner's policy, it may be protected even if the property is stolen from your car when you are away from home.
Before placing a claim against your home insurance policy, check your car insurance policy first. If you have comprehensive car insurance, the contents of your vehicle are covered, and you can file the claim against your auto insurance policy. You should compare the advantages of using your home insurance versus the comprehensive, as your auto insurance premiums may increase after a theft claim, but your homeowner's policy probably will not.
If the car is completely stolen, it is covered by the auto insurance, but any contents of the vehicle can be replaced using your homeowner's policy. If you choose to use both car and home insurance, remember that you will be paying he deductibles for both policies as well, so make sure that what you are trying to replace is worth the added expense. For simple theft, such as a CD collection, it is probably cheaper to avoid filing a claim completely and just buy the replacements out of pocket.