My perfect night would only be able to occur if I had a massive beanbag chair (which I intend to buy fairly soon, after my wages this month come in and I can get a relatively cheap one from IKEA or Argos). It would also require me to have a girlfriend, or at the very least a girl who could possibly become my girlfriend (as this could easily work as a date or something). Oh, and my two flatmates would have to be completely not present too (don't get me wrong, I like spending time with them, but in my perfect night it's basically quality time with my hypothetical girlfriend, so yeah...).
It would basically consist of me and this girl sitting together on the massive beanbag chair, with a thunderstorm raging outside, mugs of hot cocoa in our hands, with the lights off, watching a DVD (ideally a romcom, as unlike most guys I do actually enjoy so-called 'chick flicks').