I myself do not really view “What is to be Done?” as a great beginner work for Marxists, since it mentions a lot of obscure philosophers or groups that a modern audience (with their cursory knowledge of Russian history being from the lips of liberals, or worse, conservatives) would hardly know the context of, and I am reading a version that has notes on these people!
That is not to say that it is not an influential or essential work of Lenin (I think it might be up there with “Imperialism, the Highest Stage of Capitalism” and “The State and Revolution” in terms of either factor), but one has to be willing to trudge through Russian names that you will likely never hear again.
Ah you have a point with a small amount of truth mixing into the soup of atrocity fiction, and it honestly makes their propaganda stronger than it normally would be (because sometimes that truth is miscontextualized or exaggerated beyond absurdity, like the quote from Marx saying he is not a Marxist being used to make people believe he stopped being a Marxist when I do not think that was the original context of the quote).
I definitely know of those two, but I have not gotten around to watching them much (I probably should some day).