how many files/folder on disk root/in a folder for a shared folder ?

hi,

I'm currently migrating a huge number of files from a "foreign" file
system (OpenVMS + Pathworks, Patworks=Digital own implementation of
share folder, similar to Samba) to a 2K3 server.

those files were organised in 6 share folders, each one containing many
(~2000) subdirectories, one per day since many years.

my idea was to have only 1 share folder and all the one-per-day subdir
in it.

how many files/folder may I reasonably put on a disk root ? and in a
folder ? and in a shared folder ?

I mean, is there a limit beyond which the system will stop to function
correctly ?

TIA,
Pierre.