Are your outlets grounded or not? In some older homes the proper wiring might not be in place, and it is possible that a previous owner installed a grounded receptacle to replace one that wasn’t. Without testing the outlet for a proper ground, you will not know if the outlet is a potential hazard.
What are the risks?
If an appliance plugged into an outlet that isn’t properly grounded has a short, you might become the ground and suffer electrocution. There are simple, cheap devices that will check the ground, or you could consult an electrician to test the outlet.
If you find out that you are not wired for proper grounding, you have the option of installing ground fault circuit interrupters (GFCI) which still protect against electric shock even when not connected to ground.
You should not try to make modifications to your electrical system on your own. Although hiring an electrician will cost you more, it is worth it to keep you and your family safe.