My phone is plenty old, but so far, I had no specific reason to buy a new one. It could be used for phone call and sms, and that was good enough for me.

But now I really want to get a new phone, solely to try out some Virtual Reality! This VR-stuff is the essense of what was supposed to be cool about the future. So while I don't normally care for hardware, this is something I really want.

So which phone is the best here? And which VR headset? I have a feeling that there's more programs for Android phones, because of Google Cardboard.

Currently I'd say the best one would be the Galaxy S6 / Galaxy Edge S6 / Galaxy Note 5 paired with the Gear VR. Cheap if you already own one of those phones as the VR is only $159(AUD) - but ONLY works with those phones

Thanks, I'm checking those phones out - look like they all runs at 1440 x 2560 pixels.

The reason I suddenly got interested in VR was that I bought a VR headset for 150 kr. (that's 22 $) in a local supermarket and it actually worked fine, but my HTC Wildfire was too outdated to run any of the VR programs.

S6 / S6 Edge, Nexus.

Why would you need VR with phones? In 2 hours yourbattery will discharge. I would rather spend my money on the Occulus VR.

Buy the most expensive one because they release one every few weeks and hope VR was on their list of gimmicks to cover?

I'm totally newbie regarding this new tech. But since those phones and Oculus Rift are both created by Oculus, they seem to offer kinda the same:
http://www.gizmag.com/oculus-rift-vs-gear-vr/35420/

Oculus Rift is an open system, as should be expected for any PC hardware. The Samsung phones, on the other hand, are closed ecosystems. Much less fun. This is the major thing to consider, IMHO.