2001: A Space Odyssey was written concurrently with the development of the film. This is covered in the Development section of the Wikipedia article, for example:
Early drafts included a short prologue containing interviews with scientists about extraterrestrial life, voice-over narration (a feature in all of Kubrick's previous films), a stronger emphasis on the prevailing Cold War balance of terror, a slightly different and more explicitly explained scenario for Hal's breakdown, and a differently envisaged monolith for the "Dawn of Man" sequence. The last three of these survived into Arthur C. Clarke's final novel, which also retained an earlier draft's employment of Saturn as the final destination of the Discovery mission rather than Jupiter, and the discarded finale of the Star Child exploding nuclear weapons carried by Earth-orbiting satellites.
See also this note:
The novel version of 2001 featured the journey to Saturn instead: Clarke acknowledges this retroactive continuity in his author's foreword.
In terms of the destination of Discovery One and location of the second monolith: they will inevitably be the same in a given version of the story, because otherwise it makes no sense ("But wait, if the monolith was discovered on X, why are we headed to Y?").
I don't know about renaming HAL, this may have been a translation issue (perhaps, following the film's success, the name was famous enough to not need translation?)