To my knowledge the hoses are sort of a quick release type hose, that require a special tool to remove.
From what I can tell, it sounds like your heater core is clogged up.
If you use regular heater hose in the replacement, your going to need the following.
5/8 to 3/4 heater hose adapter
The engine connections are 3/4 and the heater input/output is 5/8.
Or you can just get the OEM versions.