Need to pick some of your Linux users brains.

I'm wanting to rid myself of Windows server 2008r2 as my primary home server.  I'm letting my Tech sub expire plus I'm just flat out getting tired of the instability of the winblows server period.  I have to reboot it on avg about once ever few weeks at least.   What version of *nix would ya'll recommend I replace my win2K8 server with.   I will need the following features,  PDC, File sharing and single sign on.  So I'm guessing I'll need some sort of Samba and LDAP combo of setup to do this.  Most of my clients are Win7 clients atm with a few Fedora and Debian based clients as well.  I also have a few media devices that will just need to access some shared folders for music and movie files,  these devices are items like blu-ray players, xbox, and Dish Network Hopper system.   Any help would be greatly appreciated.  

Also a good write up on the setup for the Samba and LDAP configs would be great as I haven't dealt with the combo of those before, just a limited Samba share setup long ago.

Most of my *nix experience has been with remote dedicated servers for web use and also development and desktop type use boxes here at the house.

R.F.