Russia would still not be able to become capitalist in the Western meaning. For a democratic Russia to survive, they'd need to attend all the social problems Russia faced. And enact a land reform, the only way to get peasant support, and most Russians were peasants. Also, in a democratic Russia the Mensheviks and Left SR would still be strong influential parties.
I'm not sure that non-communist Russia (let's leave the $1 mln question how the country escaped Bolshevik rule outside of discussion scope) would have it's ups and downs in sync with rest of "civilized world". The country is so big and so relatively unlinked to world economy (Russian industries pre-1914 were driven by internal demand and it's Asian export markets much more than by trade with West), it always tended to have it's ups and downs independently. It will be heavily weighted down by external debts post-WWI (to the magnitude it might declare itself bankrupt, although this is not too likely), so it might very well spend 1918-1925 recovering. However, market meltdown of Depression could give Russia golden opportunity (exploited by Stalin IOTL) to buy Western equipment and know-hows at deeply discounted prices in 1930-1935.So, Somehow the russian revolution is changed from communist to democratic, they manage to reform to the point where they the same economic boom the west recieved in the west. How does Russia and it's people react to this?
However, market meltdown of Depression could give Russia golden opportunity (exploited by Stalin IOTL) to buy Western equipment and know-hows at deeply discounted prices in 1930-1935.
Well, that's a good one. However, grain was still selling, even at the height of Depression (where do you think Stalin got his money). It is just that discounts were pretty steep. And it isn't like Czarist Russia haven't had this legacy of selling grain when parts of it's own population were starving ("we will starve, but sell" mantra was repeatedly used in 1900-1913).Buy with what? Russia was a commodity driven economy, in terms of foreign currency.
If Russia stays capitalist, then the Belgian and French investments there will remain, preserving Russia's financial infrastructure, and the Ukrainian grain trade will continue, giving Russia foreign currency to service its debts.
Without Russia's repudiation of its debts, Britain and France won't be beggared to the same degree, so will be able to repay the US in turn. This will reduce the intensity of the reparatins issue.
All in all, there probably won't be a Depression. Russia will continue to industrialise with western capital and gradually modernise its agricualture as it proves profitable.