This winter I have noticed my temp gauge just below 1/2 way mark which I think is normal. Lately with the colder than usual weather, I have seen my gauge not move at all. Tonight I drove about 23 miles at highway speeds (65-70 mph) and stopped for some fuel. The temp gauge went up to about 1/4 and as I drove another 20 some miles, slowly got colder. I am thinking a thermostat is stuck open (or missing) Any other thoughts?

as long as it is not overheating, I will most likely wait for warmer weather to change the thermostat. I'd hate to work on it in 20 degree weather (or colder) Heater is nothing to write home about, it gets me by but doesn't get warm enough to require me to shut it off or cool it down.

 

Sounds like the T-stat is stuck open. If you can read the actual temp via the OBDII port that would be the best. Replacing the T-stat is pretty easy.
Siphon out a gallon or so of coolant from the radiator.
Pop off the upper hose at the engine.
Remove the two bolts for the T-stat housing.
Replace and reverse the process.
You can do it when the engine has warmed up a bit so your hands don't get so cold.

 

Yes, replacing the T-stat is easy, it took me a total of about 5 minutes - hardly enough time to get cold hands! Now we regularly turn the temp down inside, before it got just warm enough to keep the windows clear.

 

The last thing you want to do is overheat, and then be scratching your head over those pesky head gaskets... The dash temp gauge is only there for decoration. Get yourself an ultragauge, and keep an eye on the temp real time. Best sixty bucks you will spend on your rover.

 

You can also get something like this for your phone.
Amazon.com: Bluetooth OBD

 

I don't have one of those new fangled phones. Mine just makes phone calls..

I pulled the thermostat today and replaced it with a 195 one. The fool at the parts place wouldn't sell me a 180 t-stat. He said it wouldn't fit.... Last time I go there!!

The one I removed had a 66 on it which I assume is a 150. Probably a bit too low for these parts. Hope it is not an indication of overheat problems..