Giving the Ukraine as much military support as we can without direct involvement and continuously increasing sanctions against Russia is the best solution I can think about.
The ethics of this isn’t easy.
That why I think the solution to “smash windows in Russia” is stupid. It will effect average Russians, not businesses, the government or the military. They have IT department, staggered role outs, update cycles and so on. Software that “bricks” a PC won’t penetrate the entire nation at once or actually brick a device. We are talking about PCs not mobile phones. Besides, it is windows, those users are used to reinstalling. I would also be surprised if there is any relevant military hardware out there running windows. I get a strong vibe of “why do the Russians get to steal Windows and I still have to pay” from the original post and find his reasoning unethical and spiteful.
While it's moral on a larger perspective, this will directly cause the death of people in Russia and the West (never mind the harvest in Ukraine that probably isn't happening and will cause famine in the third world). Just because no missile is fired doesn't mean the effects of the sanctions will be without victims.