Sonic Adventure is not available on PlayStation 3. It launched on Sega Dreamcast (1998) and was ported to PC (2003) and GameCube as Sonic Adventure DX: Director's Cut (2003).
Downloading ROMs/ISOs for games you don't own is copyright infringement. Dump your own discs (Dreamcast: use an SD adapter + DreamShell; GameCube/Wii: CleanRip).
Verdict: PC (Steam + Mods) is the best balance of accessibility, quality, and features.