In the present paper we investigated two families of RP 2D perovskites including linear monoammonium cations, namely (CnH2n+1NH3)2PbBr4 and (CnH2n+1NH3)2PbI4 with n=4, 6, 8, 10, 12, 14, and 16. While previous investigations addressed some structural and optical data on the iodide-containing system, this work provides the first detailed investigation on the (CnH2n+1NH3)2PbBr4 series, also including a comparative study between the two series. XRD and Raman analyses evidenced similar structural features for the two systems at room temperature, with the bromide compounds characterized by a series of transitions occurring at lower temperatures, as evidenced by DSC measurements. Optical properties confirm a general blue-shift for the (CnH2n+1NH3)2PbBr4 system with respect to (CnH2n+1NH3)2PbI4. PL data show that, interestingly, the investigated 2D investigated possess two distinct variation paths for their excitonic emission behavior, one directly related to the chain length, influencing the interplane interaction between organic layers, and another one depending on the ammonium coordination to the halogen atoms (polymorphism) which directly depend on the temperature of the system.