He told me that he wanted to get "a fighting film" for his brother and picked up a copy of the latest Tony Jaa DVD in HMV, then started looking for a "Mummy film" and eventually decided - I know not why - on My Super Ex-Girlfriend.
This is not a bad choice actually as his mother his big fan of both Uma Thurman and Eddie Izzard. I haven't seen it myself, but IMDB summarises the plot as follows:
Our boyfriend (Luke Wilson) is coerced into asking a seemingly harmless, pretty young lady (Uma Thurman) out on a first date. Little does he know that she is a vengeful, spiteful, rather overbearing woman masquerading as a normal citizen
That's probably going to be mined for hidden significance come Christmas morning.
Another very modern dilemma I had to confront on the same trip is how to react when your little boy decides that a quick game of hide and seek is just the thing to break the monotony of a shopping trip, and conceals himself in the erotica section at Waterstones.