97k is a good time to replace the plugs. You're right! They probably need it...
I recommend the factory Motorcraft spark plugs.
Its hard to say if that is related to your check engine
light being on though.
CEL on is usually related to a failure of the emissions system somewhere. If your car seems like it's still running good it probably won't hurt anything to drive it until you can get it repaired.
If you can retrieve the code and post it, we can try to narrow down what the CEL is trying to tell you.