Radiators (steam, water, glycol, mineral oil) or something else?

We have radiators so there's no ducts, but the blinds are right above a radiator.

Heating is Electric by old radiator or fireplace with natural gas, and A/C window units though out the house.

Bleach the tub and tile, paint the radiator white with oil based enamel spray paint

The radiator around the homes are also good.

First make sure there is nothing like heating ect. that are making these noises (e.g. radiators need to be bleed). 

All radiators on first floor look ok.

Steam radiators have bigger usually steel radiators but old hot water furnaces can also have a slightly smaller steel radiators. 

Many will argue that hydronic gives a "nicer heat" because it does not dry the house to the degree a forced air system does.Most hydronic systems found in houses use baseboard or radiators  which suffer from the same problem as any form of convection heat - slow recovery time.  

I'm looking at a property tomorrow for a flip, and the heating in it is the old style radiators.