The best way to play GTA IV at this point is piracy - repack includes tons of bug fix / QoL improvements and performs better than the stock game with the included
Amazon.com: Grand Theft Auto IV : Video Games
Grand Theft Auto IV - GameSpot
GTA IV (v1.0.4.0) PATCH DOWNGRADE file - Grand Theft Auto IV - Mod DB
IVPack - GTA IV vehicles in GTA V - GTA5-Mods.com
GTA 4 Complete Edition (XBOX 360) : Rockstar Games : Free Download, Borrow, and Streaming : Internet Archive
Grand Theft Auto IV Patch Download
Grand Theft Auto IV: The Complete Edition - PC : Free Download, Borrow, and Streaming : Internet Archive