Dolby stereo tracks (such as Temple of Doom) were mixed for a 4.0 channel layout - left, right, centre and rear (of course large theatres would present these channels across multiple speakers to ensure coverage of the listening space).

The 'stereo' part is admittedly confusing because we tend to associate this term with 2-channel presentation, but indeed these tracks are best experienced in a surround capable setup; 5.1 presentation is really not that great a leap from 4.0, as the additional channels simply provide 'split' surrounds (for panning of rear effects/music) and a dedicated bass channel.

For as pure a Dolby Stereo experience as possible, switch your 5.1 receiver to Pro Logic. This will steer the left, right and centre from the mix to the correct speakers, and send its 1-channel surround to both of your rears. Your subwoofer won't be neglected, since your receiver will filter off the lower frequencies of the mix for it (DS mixes don't tend to be all that bass-heavy, but they can surprise you).

You might want to give Pro Logic II a try - it's an altogether cleverer decoder than the original Pro Logic, and simulates stereo surrounds (basically upmixing the 4.0 source to full 5.1).