Water pump went out today.

[ScottStu]

So, about a block from home the water pump went out. Temp gauge went up to the "0" on 180 and the warning light came on. I already ordered a new pump (one with the plastic impeller) but what kind of coolant do I need? Also, how much do I need? I was reading that you should clamp off the hoses or should I just drain it and start over.
Hopefully it will warm up here in Denver (its snowing right now) since I have to do it under the carport and not in a garage.