SH1 is also available on PSP, PS3 and PS Vita.
SH2 is on PS2, Xbox and PC.
SH3 is on PS2 and PC
SH4 is on PS2, Xbox and PC (I believe Japanese PSN accounts can buy it for PS3)>which Resident Evil should I start with
RE1, the original. There are multiple versions to choose from, like Saturn (has a battle mode), DS (has a new mode), PS1, and PC (mod for Ultimate Uncut version)
Just play it in release order, including Survivor and Outbreak games (as well as Biohazard 4D Executer), and when you hit RE4, play chronological order (don't do the RE6 chronological autismo shit though)