My first suggestion would be
Dwarf Fortress (I suggest starting with the
Lazy Newb Pack). It's really two games in one. There's an adventure mode where you're free to just wander around, recruit some companions and kill whomever or whatever you please with one of the most detailed combat systems ever made that'll allow you to choose which part of your teeth to bite your enemies with:
There's also a fortress mode where you (indirectly) control a bunch of dwarves as they try to set up a new place to live. You'll have to set up workshops, bedrooms, farms, kitchens, eating halls, temples, inns, etc. to keep your dwarves happy and dig ever deeper to mine the metal you need to equip your soldiers for when you'll inevitable get attacked by goblins, forgotten beasts or those damn elves who got pissy because you chopped down some trees.
I also found two free to play driving games:
Crossout is a free to play "post-apocalyptic MMO Action game" involving driving that's described as "Like if Mad Max and Twisted Metal had a baby in a sandbox”.
RaceRoom Racing Experience seems to be a regular racing simulator.
Assuming you have a touchpad, you can also try one of the many free to play MMORPGs out there. A lot of them don't require fast or accurate mouse movements.