A healthy, regular lead acid battery is considered only 50% capacity at 12.2 volts. Anything less than this and I'd be very surprised if there's enough energy to turn an engine over at sufficient speed to start, if at all.
It's also important to measure the voltage while the starter is engaged, this will give a good indication on the battery health, assuming it's been fully charged first.
Get the earth/battery cables sorted first and see if you can get it turning over at a reasonable speed. Worry about sparks and fuel later