One cause for a blown fuse (or tripped breaker) is a short circuit. That means that an appliance plugged into that circuit is damaged, or it could mean that the wires in that circuit are damaged.
To determine if the problem is a damaged appliance, unplug everything on that circuit and see if the breaker will reset (or see if the replacement fuse holds). If the breaker will reset, the problem is in an appliance. If it won't reset, the problem is in the wiring.
Whatever the problem, do not use the appliance (or circuit) until repairs have been made.
Also, see the categories Grounding, and Safety.