Biggest problem with pulling the t-stat is that it will take longer for your car to warm up = crappy gas mileage. Additionally, when you're driving on the highway with plenty of air flow through the radiator, your engine temps may drop to below the normal operating range. Again, crappy mileage.
A low temp t-stat will let your engine warm to normal ranges and keep your engine at the cool end of the operating range on the highway, but in city driving the temp will still spike until the fans kick on because there will be insufficient air flow through the radiator.
The only solutions left for your are:
1. Lower temp thermostat - a 160 or 170 should do.
2. Your temp gauge and/or wiring may be faulty.
