All my partitions are either ext3 or ext4. This is the first time I've seen the white background style Advanced Permissions window. Until today I've always seen the style shown above.
Really don't know ... never used any GUI for permissions ... ls -l is my tool

As I see in the white background dialog, it is possible to add permissions for additional users, individually ... IIRC this is supported from ACL feature (access control list), available as mount option acl. see man mount and man acl.
cat /proc/mounts will show the acl option, if used.
On my system acl is enabled for ext4, but not for ext2, do not have ext3 fs right now ...
[root@fatman ~]# cat /proc/mounts |grep sd/dev/sda13 /share1 ext4 rw,nosuid,nodev,noatime,barrier=1,data=ordered 0 0
/dev/sdb6 /share9 ext3 rw,nosuid,nodev,noatime,errors=continue,barrier=0,data=ordered 0 0
/dev/sdb9 /movies ext3 rw,nosuid,nodev,noatime,errors=continue,barrier=0,data=ordered 0 0
/dev/sda12 /movies2 ext3 rw,nosuid,nodev,noatime,errors=continue,barrier=0,data=ordered 0 0
/dev/sda5 /home/polack/Documents ext3 rw,nosuid,nodev,noatime,errors=continue,barrier=0,data=ordered 0 0
/dev/sdb5 /home/polack/Documents2 ext3 rw,nosuid,nodev,noatime,errors=continue,barrier=0,data=ordered 0 0
Don't know what I'm looking for. As far as I know, ACL is a Windows thing.