Geneva has good street spots, you can explore the city and you'll find fun shit to skate everywhere.
Lausanne has good spots too but it's well hilly (which is not a bad thing at all). The bowl by the lake is rubbish.
Yverdon has a big skatepark with a good bowl.
Montreux has a good indoor park if it's raining.
There's a new skatepark in Sierre indeed, but it's not 2 hours away from Lausanne, it's closer (just over an hour).
Just over Sierre you'll have Alaïa Chalet too, a big indoor and outdoor skatepark where Chany works these days.
There's a good bowl and a fun pump track in Le Châble, between Martigny and the Saint Bernard Pass, where you'll have to go when leaving southern Switzerland for Italy.
Bern has Bernside, a good bowl built by the locals.
Where exactly are you going and what do you want to do or see?
I was born and bred here, I should be able to point you in the right direction.