1) In WW1, the Germans never let Lenin out of exile. Say he randomly dies. The Bolshevik party never take over, and go into an alliance with more moderate socialists. The Duma runs Russia after WW1. Communism never takes root in Europe.
2)Woodrow Wilson persuades Lloyd George and the French president to offer more moderate terms to Germany with the Treaty of Versallies.
3)Without the fear of Communism, and with Germany better surviving the Great Depression, Hitler never comes to power.
This leaves the remaining axis powers Italy and Japan.
Mussolini would have still come to power however, and would still invade Abyssinia in 1936. If he does anything else though is questionable. He would probably help General Franco come to power in Spain with the Civil War, and maintain the Spanish as allies in order to counter-balance Britain, France and perhaps Germany. However, it's clear which side as the more power and if anything does kick off in Europe it would end with a swift Anglo-French victory.
As for Japan, the British Empire and her Dutch allies easily counter-balance any imperial ambitions Japan may have. Japan would probably still invade China, but it would not get into SE Asia or the pacific. Eventually, the Japanese army would be weakened by a prolonged war with China and would probably eventually withdraw.
A "WW2" of sorts could however happen if Italy+Spain and Japan go into an alliance and agree to attack the British and French Empires simultaneously. While that would be a big war, it wouldn't be anywhere near as severe as WW2. Britain and France would destroy the Spanish and Italian fleets and then make a successful land-invasion in the space of about two years.
Then Anglo-French forces would launch a counter-offensive against Japan in the Far East. The Japanese navy would be tough to beat, but i think it would eventually overwhelmed by the sheer size of Anglo-French navy sent against it. Then it would be a case of starving Japan into a negotiated peace settlement. So you would be looking at a major war, but a war not near as destructive as WW1 or WW2, but lasting around the same time length as WW2.