Mitsubishi Repair: Heads, head gasket replacement, mitsubishi gallant

Question
I have a Mitsubishi gallant 2001 and the oil and water is mixing. I don't know rather i need a head gasket or just a whole new head. Also my car continues to get hot and have bin sitting for about 3 months. When it gets hot it starts to smell like antifreeze i have put a new radiator in my car and it still is running hot i have bin getting prices from over mechanics and they say between $800-$1500 to repair not to mention find why it is getting hot. What do I do?

Answer
Rachel,
The prices quoted are pretty standard for a head gasket replacement.  It's very labor intensive and needs to be done carefully as to not damage any internal components.  The odds are your mechanic will remove the head and inspect it for damage.  If they have to replace a lot of parts or if there is excessive wear, they may just replace the head with a rebuilt one.  If they reuse the old head, they will be need to machine it (i.e. smooth down the mating surface so it makes 100% contact with the block).  Your engine, like most today, use an aluminum head with an iron cast block.  Since they are two different metals and they behave differently at high temperatures, your head can warp since your engine is running too hot.  

Water mixing with the oil can be caused by a bad head gasket.  Overheating is also a result of this, so by replacing the head gasket and refining (or replacing) the head should also address your overheating problem.  
Good luck!