Was going to recommend this.

Civ 3, why anyone would waste time on 4 or godawful 5 is beyond me.

Minecraft

Doom. Good and simple. I can even send you my folder ;)

Gemini Rue 
(which looks like it's from 1990 but actually was released only two weeks ago; very good indie p&c adventure game with a strong Blade Runner and Beneath a Steal Sky vibe; I'm currently playing and enjoying it)

Beneath a Steel Sky is a good recommendation on its own imo, mainly because it's still a good game and freeware now.

Or one of those many other great games available on GOG, e.g.
- Barozi's recommendation (which takes your life and then some) or its successor which was released on GOG today
- one of my all-time most favourite games (I like it far more than Caesar III, which seems to be more popular though)
- a game from the Age of Wonders franchise (GOG got 3 of them)
- which is the spiritual successor to another one of my all-time most favourites
- or how about this legendary TBS franchise or this one

Or any of the 4 free ADG King's Quest/Quest For Glory remakes, which will drive you mad (don't believe the "soon!" button on KQ III Redux, in fact it's already been released recently).

As I've never played a game with a touchpad only, I don't know if a p&c adventure game would actually work, so like others I'd primarily recommend turn-based strategy or a city building/economic sim.

In case you're not interested in any of those, then here's a special tip which should definitely work with a touchpad and probably ruined more lives than Civ and HoMM together: Peggle.

Kings Quest, Quest For Glory, Police Quest, Space Quest...Anything Sierra will work.

Wizardry as well (anything Sir Tech of course)

Im not biased at all...  But all the turn-based games (Etherlords, HMM and so on that have already been suggested work too)

Personally I can recommend Baldur's Gate II and Rome: Total War, but I suppose the first Baldur's Gate or any other Total War game won't be any worse either (of course I doubt your laptop can run newer Total War games). They're a bit tedious to play that way but then again, I found Civ IV to be on roughly the same level when I tried.

Progress Quest

Viva Pinata!