Normal or not???

Hi i'm a new user from quebec city...I do my mechanical study...My english is not very good but...There is...
I have a pontiac sunfire 95 4 doors....And i have some questions about my sunfire...The gauge for my wwater temperature always go on the last white stripe on the gauge....And after that, the fan start to blow....There is a problem with the gauge or the fan is starting to late or...other...My water pump is good,thermostat good, my motor head is good,my radiator good too....And i have another problem...I dont know is its my tranmission or ohter....I have a tree speed automatic transmission with overdrive...And a 2.2 motor...And when the temperature ghauge goes to the last white zone again, and im driving 60mph or over and go to an exit on the highway....And stop on a stop or a red light my sunfire stop....I start it i move the shifter to the drive position and he dont want anything, he stop....To go to the drive position i need to put the rpm to 3000 on neutral or other and after take it to the drive position...Did you have an idea what it could be???A problem transmission o a motor problem???
Help me!!!