Seeing all these ten best, it seems sad to exclude Andrei Tarkovsky, who only made seven feature films in his life.  So, excluding student films and shorts, here's my ranking.
1. Solaris
2. Andrei Rublev
3. The Mirror
4. Nostalghia 
5. My Name is Ivan/Ivan's Childhood
6. Stalker 
7. The Sacrifice 