I won't spend too much time reviewing the actual films because chances are you already know what they're about. I will say however that they are very good films and worth owning if you're a fan of Batman The Animated Series. Subzero came out a few years after the show ended so it is slightly different but overall it's pretty similar.
As for the DVd.. I just bought this off amazon.ca and it arrived today. In the picture it shows 2 discs. However, it is only one disc, a double sided disc, one movie on each side. So just know that before you buy it. I heard the quality for double sided DVDs goes down for the content and I'm not sure if this is the case here but I wouldn't be completely surprised. It's good quality but I thought my Batman TAS dvds had better quality than this.
Anyway, good purchase for a good price.