In the winter, mine runs between A-B (40c) and in warmer weather when idling it will go between B-C, but regular driving A-B. If you have not flushed your cooling system or changed your fluid, I would suggest you do as coolant will break down after two years. Also, take a hose and rinse out your rad. Mine started running a little warm last summer and a simple cleaning of the fins on the front and back of the rad returned everything to normal. Make sure your fan is also comes on to ensure it cools when it needs to. If it doesn't, your fan is either faulty, your coolant sensor is faulty, or the fuse is gone.
As far as antiseize, it is used on the threads of the plug to stop them from seizing in the head, making removal easier. If your plug is a grayish tan to white colour, that is normal. Use this as a guide.
http://www.bullittarchive.com/Mainte...g_Spark_Plugs/