Does your temperature just keep rising up when you start the vehicle and level off at the white mark (which is 235, way too hot for comfort)? Put another way, when you start the vehicle when it is cold does it continuously go up all the way to 235 then stop, or does it slow down once it reaches 200 and then gradually increase?
If your thermostat is damaged, it may stick shut and not open until a much higher temperature than it should, so even if the rest of your cooling system is in top shape, it will still run hot. Does your temperature stay at 235 on both the highway and the city/idling?
Tell us as much as you can about the symptoms, if it ever cools down when driving, if it runs hot with or without a/c or both, etc. Do a search for this, there are THOUSANDS of posts regarding this problem. Hoses, fans, fan clutch, radiator, water pump, tstat, head gaskets, a/c condensers, belts, the list goes on can all contribute to this problem, but by giving us every bit of information you can about your specific problem will really help narrow it down. Like I said before, if your system always stays at 235 once it warms up it seems like a bad tstat.