If you like SF you can't go wrong reading all of Asimov IMO. The entire Robots/Empire/Foundation series is fantastic. It doesn't mean you can't also read other, "better" SF either. Asimov's main SF work will take a few months to read at most.
Regardless, stopping at the first book is a good recommendation. Asimov demonstrated he didn't understand what made his own work interesting. Granted mystery boxes are hard, but he took an immediate about-face on psychohistory and retconned any bit of intrigue with rather vanilla stuff. The first book is outstanding.
Lucas and Disney couldn't help but copy even these bad parts of Foundation in the Star Wars prequels and sequels.
Even his contempories were better - Bester and Simak run rings around him.
The first book Orwell wrote is pretty good as well. Down and out in paris and london. It's a good picture of life in the slums at the time, and much more raw than other accounts - Orwell seems to have simply recounted his experiences.
It's a bit low for Asimov to just say Orwell was slumming it like a modern hippie. He was slumming it like in the olden days, and starved for weeks.
