Just out of curiosity, Lizzie.......had Hitler not gone on the invasion and war course (he probably would have still had Austria) what do you think would have happened to Germany. Would there have been a holocaust as we know it, or would he have done an Idi Amin and just booted out the jewish populace.
Purely hypothetical, I know, but interested what you think would have happened 
A very good question!
That is what we call counter factual history, and it is very difficult to say what could have happened or not.
However terbert, my opinion is war was inevitable as Hitler knew he did not have the oil or mineral resources, let alone financial backing to keep his administration afloat, and the grand projects promised to the German people alive. He had built his Reich on the principles of superior Arian Germans who should never 'put up' with inferior people within Germany who, he believed, had wrecked it's power, wealth, and reputation by their greed and politics. He had built up a military determined to win back German losses sustained with the Versailles Treaty in 1919. He promised the German people to regain all those, and the pride of Germany. He had no choice than to use his power and military might, although top German Generals reckoned heir forces would not be ready for war until 1941. Hitler was a chancer, an opportunist, who would never settle for a lesser Reich.
To answer your question; yes he would have kicked out all Jews, Communists and other "undesirable" if he had not gone to war, and without acquisitions of other lands he would not have had the problem that six million Jews represented that they had gathered during their conquering. The Holocaust in it's final form would not have happened, as the rest of the World would not have been on the back foot and would have given all exile's, in a relatively small number than actually occurred, of the Reich shelter, as indeed many Germans themselves did to escape Nazism during the 1930s. We must never forget though that Stalin hated Jews as well and may well have also followed Hitler's lead and ejected, or worse, them from the CCCP.
But, as I stated before it is all counter factual history which at Uni we were encouraged to study, but for me that is pointless (and I said so!) as what actually happened IS history, not some day dream on "what if"!
To me Hitler had to exist as he did. Call it fate, what is planned, or the work of the Devil, that is up to the observer to decide. The facts are he did exist, and did what he did, that has (hopefully) taught mankind valuable lessons for the future, providing those in the future do not decide to ignore those lessons from history.
What is happening in Germany, and elsewhere, including the UK, is / will really put all that to the test.
