I've been running Zoneminder on Server 12.04 64bit. I chose 12.04 because it was stable, LTS (Long Term Support), and seemed like the sensible option.
If you're dedicating a box to Zoneminder consider Ubuntu server rather than desktop, as all of the ZM installation can be done via shell using SSH once the operating system has been installed without the overhead of a desktop or the disk space usage of unwanted apps.
Once the OS was installed the ZM box went into the cupboard, got connected to the network, and I did the rest from the comfort of my lounge using my laptop.
I also opted to install Webmin for web-based admin although I hardly use it.
My path to 1.26.4 Zoneminder was via some excellent instructions titled "Ubuntu Server 12.04 64-bit with Zoneminder 1.25.0 the easy way" by bbunge, which I had been running for over a year, and then more recently in this forum how to upgrade that to 1.26.4 which is here:
http://www.zoneminder.com/forums/viewto ... 30&t=21524
(I can't remember where the 1.25 instructions were - try a search (they might be in the Wiki) should you need them.
Whether following the upgrade to 1.26.4 instructions alone will be enough for a fresh install I don't know, as I've not tried it.
But as to your original question, I've got no complaints with Ubuntu Server 12.04 64bit