I suggest you watch BB 2/3 (currently onto Episode 29 out of 32)/6/10/11 and 17 for BBUS.
For BBCAN, BB1 and BB2.
Though BBUS is very spoilery because they like bringing back former houseguests (they call it like that there) to play again or come back for tasks, especially in the second half, so I suggest you watch in order from BB2. (BB1 is boring, and is the BBUK format).
Just avoid BB9 and BB19 (the most recent season) as they are both very bad, and with BB19, some bullying can be really sensitive. Also avoid BB15 because half of the cast are racists and homophobes, and the insults are unbearable.
BBCAN 5 is a good season, but half of the cast are all-stars so don't even bother. Also watch BBCAN in order.
haha I only watched PBB, BBUSA, BBUK, BBCAN and 31 days of BBAUS 2013 (before I quit, because the episodes were too long).
The American and Canadian BBs are very different so I think you should give them a chance, there are only max 35 episodes per season, so it does't drag out compared to BBUK. I only watch English speaking BBs besides PBB.
