The Inspirion Duo comes apart in the same way as almost every other PC in the world: take out 90 (not really) screws from the back, turn the computer over, take the keyboard out, take out some more screws, then remove the top panel.

A common trend in PCs which we would love to see in other devices: many of the screw-holes are labeled to assist in reassembly. This hole is for a M2.5x8 screw.