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Rasspbian should see you OK I reckon.
If you're running headless, remember to create an empty file named ssh on the /boot partition when you burn the image.
If you're running wireless, also setup wpa_supplicant (using wpa_passphrase let's you add an encrypted password)
Maybe also consider sheeting up dhcpd.conf with a static IP for wlan0 to make it easier to find on your network
What is the recommended distribution for a raspberry pi for running various software (sabnzbd, sonarr, openvpn, samba, etc)? Will probably be running headless (if it's easy enough to install this kind of stuff without a GUI).