Should I just go and burn the DVD as a test to see if it's working correctly or not?
then post a screenshot of your flowchart if it doesn't work correctly.
>Blu-Ray DVD with a 2 and a half hour
No such thing... it is either BluRay or DVD... the only way you can put BluRay on a DVD is for "about" 20 minutes, and then it will only play back in a BluRay player, not a DVD
Make sure you have NO overrides set, and be very careful how you place your end actions