The family of hardware components that gives you fewest number of modules required to read 32 temperatures is the Terminator I/O family, using the T1F-16RTD. This modules has 16 RTD inputs, you'll need two of them to get your required 32 temperature inputs. You'll need one T1K-01AC power supply.
You also need either a T1H-EBC or T1H-EBC100 network interface module. You choice will depend on what communication protocol the PC software will be using to read the data. The main difference between these interface modules is the T1H-EBC100 supports everything the T1H-EBC does, and adds Modbus/TCP protocol support.
--MikeS