I really think, despite what lessons Draco might have learnt during the last battle, he is still Draco Malfoy--somewhat insecure, ambitious, and a formerly spoiled child. While I do believe that Draco could 'turn around' after the disappointments in his allies during the battle, he's going to 'turn around' the values he believes are important, and not make new ones. He is still going to respect power, desire power, and do what's necessary to get it, only he is going to want to be a better powerful man than his father. He's going to want to make 'good' choices and gain the approval of a world he's finally gained respect for (if you wish to maintain that he HAS gained respect for the world of Muggle tolerance and the trio--which I believe he has. he seemed to have some respect for Harry in the epilogue).
However, you can respect something while still guarding independant values. He's still going to be proud he's pure, that his ancestry can be traced back so far--and I think he'd want to maintain that pride in his lineage. I think he would marry a pureblood--but not all burebloods are Bellatrix Lestrange. I am very sure there are some rational ones out there. He'll likely also marry someone of his own class---his self importance isn't going to dissappear altogether. Once Draco gets back on his feet, he's going to want to stay there, and regain his place in society.
Therefore, I will defend continually that Scorpius would be brought up with these ideals. Pride, ambition (the desire to succeed!) and the notion that his family and he himself are very important. I can't see Draco ever being a very loving and involved father (teaching his son quidditch or stuff like that. I imagine he'd find it all overly sentimental and a waste of time--he IS self important, and I don't think that will change), so I think it would be more likely for Scorpius to turn out with some of the same qualities of young Draco. He'd likely be somewhat desperate to prove himself to his father.
Since Scorpius would want to prove himself, and having been brought up beleiving that his family and his lineage was something special--if not perhaps more special than that of others, I think if he were faced with the choice between Gryffindor and Slytherin, despite being suitable for either, I think he'd choose Slytherin, believing it was the noble house, the house tied to his family's history and therefore a part of his pride. I think choosing Gryffindor would be out of the question. The prospect of choosing the unknown, the strange, and the different over what he knew was good, noble, strong, would just be foolish and somewhat wistful. Even if Scorpius were to despise his parents, I can see him still choosing Slytherin as it would promise him a chance to prove he was stronger, better than them.