<p>I have an old notebook computer that works just fine, but the outside of the lid is badly damaged and needs to be replaced. The screen and wiring are fine, so I only need to replace the housing that is exposed to the outside world.</p>
<p><strong>What is the best filament for an impact-resistant printed housing?</strong> Should I consider other options that may prevent damage to the internal components? Are there any alternatives with cosmetic benefits?</p>
<p>Edit:
Since I was asked, presume I may be willing to buy a new part to upgrade or accommodate a new filament type.</p>

If you just cared about impact resistance of the housing itself, the clear choice would be TPU, which would be basically indestructible. However, the housing is there to protect what's inside - not only from impact, but from stresses (e.g. bending) that could break it. This means you need a material that both provides rigidity and avoids breaking easily itself.
If you were doing an old (90s or earlier) style laptop case that's a tank, I'd actually say yeah, go with TPU 95A or higher (98A or so if you could get it) and add some reinforcement ribs/stiffeners. This stuff can be quite rigid at 100% infill, and it will hold up fine to heat, abrasion, even most chemicals. But if this is a modern slim style case, a small amount of material needs to provide a lot of rigidity and that's not going to work.
PLA actually fares really well here in some ways - it's one of the most rigid printable materials, and very easy to get good bonding. If you check for example CNC Kitchen's strength tests, you'll find plain PLA usually coming out on top of most comparisons. However, PLA doesn't handle heat well, which might rule it out.
ASA, ABS, or PC is probably your best bet, but I don't have any experience with them so I'll leave the part about them as something for another answerer to write.