It sounds like the wire is corroded to the plug. This is not good, however easy to fix.
Step 1) Grab the plug wires with vise-grip pliers and rip them off.
Step 2) Unscrew and remove sparkplugs.
Step 3) Replace the plugs and wires with new, quality parts.
YMMV, be gentle as nessicary.
Done.:thumbup: