There are just commentaries on (2), while there are loads of extras on (1) along with the commentries on (2). I don't know about the rutime problem, but I can assure you all the episodes on (1) are full and not edited. The third series on (1) is split into two discs, while (2) just has it on one disc, hence the extra disc on (1). If you take my advice, you should get (1) as it has much more extras. The price is higher, but I think its worth it.