PC-BSD is the obvious option targeted at desktop. Normal.FreeBSD, NetBSD or OpenBSD are also options. The Solaris spinoffs are pretty much server targeted so not really recommended.
I run FreeBSD on most things that I care about running long term these days, tho PC-BSD probably makes more sense for end-user use. I'll caveat that by saying *BSD isn't Linux, and it does a lot of stuff differently, so expect a learning curve and a need to embrace certain new ways of doing things.
1. Systemd as an alternative to Upstart and init.
2. Systemd does everything.
3. Systemd becomes more important than the distributions themselves.
I actually like their vision - I just wish my linux boxes were not part of it.