ARGH!!!!!!!!!!! I just wrote a long reply and then something happened.....and it was deleted!!!!!
OK, I'll try and write it again....DV, actually I'm not a huge Fellini's fan....he got this typically fellinianan visionary style in his filmaking that really doesn't appeal me so much. Of course the movies you mentioned are universally acclaimed but they did not strike me the way I expected. Anyway, "La strada" is a real masterpiece. And like other cinema masterpieces, it is not just cinema. It's poetry, pure poetry. With the unforgettable Giuletta Masina's performance as the naive, simple-minded, abused little Gelsomina and Anthony Quinn's brutal Zampanò. Great movie, yes. At the same level I'd rank Nights of Cabiria, once again an astonishingly magical performance of Masina as a poor prostitute in search of true love. I never understood why two absolute masterpieces like those have been almost forgotten...it's a shame! "Amarcord" is one of the most visionary Fellini's films....it won an Oscar if I'm not wrong....I don't know....not my kind of cinema.... "La notte" (aka The night) is a largely acclaimed movie of Michelangelo Antonioni (along with other early 60's movies of his, especially The Adventure, Eclipse, The red desert, on the wake of the so called "incommunicability cinema") -- definitely not my kind of cinema....

If you are interested in Italian classical movies, I'd suggest you to watch DeSica's (Shoe-Shine, The Bicycle Thief, Miracle in Milan, and most of all Umberdo D) Rossellini's (Rome Open City, Paisan, Germany Year Zero) and Visconti's (Ossessione, Bellissima, Senso aka Livia, Rocco and His Brothers, The Leopard) films. These are cult movies. So you probably already watched them. Let me know if you want some more suggestions.

Ciao!