Nothing but problems. Please help!

What is your question?

First off, noticed a while back water soaks the floor boards front and back. Recently the heat quit working when idling. Blows luke warm air but when pressing down on the gas it then blows hot air. Now the car is overheating. Does it mainly when sitting still and idling. Normally cools down while driving. But also noticed it overheats if driving interstate at high speeds such as 70 or 80 but is okay when driving about 50 or 55. Noticed that after parked and car is turned off the fans will kick on. When we Opened up place to put antifreeze noticed it was nasty looking and was bubbling. I don't think it's circulating threw at all. Normally no lose of coolant but sometimes seems to have lost some. But haven't experienced any leaks at all. What cld all this be?