still loving disco

The fuel was leaking from disco.We checked the connectors which are under the ignition coil and it was thorn so we fixed it. We thought the problem why the car was not starting was becausw of that as it was leaking fuel. When we fixed it we noticed that the spark plugs were wet. We cleaned them as we could by hand but it's still black a little bit. The injectors are transferring fuel well, and the spark plugs are connected with ignition coil well. the spark plugs are original ( platinum ) . Should I still change the spark plugs and set the new ones or what you think the problem can be?!

If the plugs are intact and there is no problem with the insulators on them then just regap them and put them back in. They aren't usually a cause of a big problem, even if a bit dirty. It would never hurt to put new ones in but if you are having serious problems it is unlikely to be solved by doing that.