Gta 4 runs well on my pc, but I am not sure Why some options in graphics tab are missing... Like Shadow quality, Reflection resolution, Reflection quality, etc:-
This bug can be fixed by updating to Patch 8 for GTA IV and Patch 3 for EFLC. From the download page for the Patch:
Fixed a bug that restricted settings changes when using modern video cards.
For the Steam edition, it should update automatically. If the game is updated and you are not running Patch 8/Patch 3, check the integrity of the game:
- From the Library section, right-click on the game and select Properties from the menu.
- Select the Local files tab and click the Verify integrity of game files... button.
- Steam will verify the game's files - this process may take several minutes.