Step outside in the cold and exhale hard, do you see white steam? Doesn't mean your gasket is blown, does it?
In the winter, exhausts do steam like that, it's a natural reaction to the cold air. But I'm not saying your car is fine, maybe you have a problem, maybe not.
What does the exhaust smell like, is it sweet? Take a good whiff. Make sure your coolant is topped off, and keep a close eye on it.

 

It is definitely cold enough for my breath to steam. However, why would my car be running rough if it wasn't something else in my cylinders than fuel? And why does my antifreeze look like oil???

 

What you showed on the driveway looks like fuel to me. I've spilled gas in the water before when filling up a boats gas tank, and the rainbow color looks just like that. If you have a blown head gasket (around a cylinder), it could be blowing combustion gases into a water jacket. Combustion gases contain fuel. That would also make it run rough, since you could be losing compression in that cylinder. Looking into your coolant reservoir, can you see any strange floaters there? Or does it look gooey at all?

 

Only thing funny in the coolant is the Bar's Leak I put in there two nights ago. It's not gooey or anything. However, when I flushed my heater core there was a bunch of brown antifreeze in there. Yuck. I just did a coolant flush 6 months ago. And it's already brown and nasty...

 

If it is cool outside, the heat from your engine causes condensation inside the exhaust system, kinda like it is raining inside it. You will get "white smoke" until you burn all that out your system. This is why people who dirve short trips or start their cars in the cold but don't run them long enough to dry out their exhaust, replace their mufflers because they are rusting out. The colder outside, the more water you get in your exhaust.

You can also take a glass of water and poor just about anywhere there is concrete or ashphalt and reproduce that rainbow effect because of the oil already on the ground.

Like 69 says, your car could have a problem or not but JMO, but you should get the dye test or pressure test before assuming the worse. If you are getting exhaust gases in your coolant, you will find your heater hoses pressurize rather quickly and have coolant dissappearing on a daily basis.

 

The reason I got really worried is because of the running rough. However the roughness could be because I just put a solid metal trans mount in my car instead of a hydraulic mount. Maybe that's why it feels "rough"....

 

The oily water is most likely a little oil picked up from the engine bay as the water washed down. I would not worry about that.

If you are burning water you will be able to tell on the plugs. Antifreeze leaves a strange looking ash on the ceramic part of the spark plugs. Also Bars leak or any other stop leak stuff like that can and will block the cores up. Those are supposed to be used once as a temp fix till you can get the real broken stuff fixed. I remember you telling me a few months ago you put some in, how many more cans of the stuff have you used?

Massey

 

Just one since then

So here's some news. I took the car to a friends house. He's a mechanic. He checked my oil and antifreeze and all that jazz. We looked at the exhaust and guess what, no white smoke/steam at all! Maybe it was condensation? And I just put a solid Z28 mount under the tranny. Maybe the vibration from a solid mount is what I think is running "rough"... Hmmmm

 

Then don't assume the worse for now. Top off the coolant and keep a watchful eye on it. Smoke/steam from the exhaust is normal this time of year. If you had been burning antifreeze due to a blown head gasket, the cloud of white smoke you leave behind would be much more noticeable while driving than it is at idle. I've seen cars go by that literally leave a blinding white cloud behind them.

 

^^ +1