It seems to me your son is telling you he loves basketball and doesn't so much love baseball at this point. I'm sure you wouldn't want to damage your relationship with him just to push him into possibly being a HS athlete in a sport he's not wild about. If he's willing to go to practices and to play, I'd pull back on being the "bad guy" and let his coaches and peers put the pressure on him to step up and do the extra work. Maybe his love of the sport will grow, particularly after basketball season is over!
As far as the xbox obsession, my youngest son is in a similar place...not all that interested in working hard at sports (like his older siblings have) but very interested in gaming/computers. We separated the two issues: required him to do something active (either a team or individual sport) and limited "screen" time. Both requirements keep his overall health/development a priority but keep our personal judgements and hopes out of it (rest of family is super competitive and sports-centric, which is likely the source of his disinterest).
Good luck and enjoy your son...as I'm sure you're well aware, they grow up too fast!