The show, while being a half-hour sitcom, is very different from BBT, which works well for the show. Firstly, and most notably, it is not filmed in front of an audience and has no laugh track. So, it has much more of a Wonder-Years-like feel, with Jim Parsons acting as the narrator. Secondly, it does not try to be a carbon copy of BBT, especially where the character of Sheldon is concerned. It is not like watching grown-up Sheldon in a nine-year-old's body. The producers and writers went out of their way to make the younger version of Sheldon different than his older self, with glimpses of who he would grow into. For example, he dressed and acted like an adult as a kid. In his 30s, he dresses and acts more like a kid. He is also not as cynical as he is as an adult, but you can see how he was starting to become cynical at that age. The show definitely would not work as well if the showrunners had not taken that approach. That said, there are plenty of references to things we eventually see in BBT, so the two shows are tied together well.
The Blu-Ray set is a four-disc set. The episodes have English captions, and the second disc includes a couple of behind-the-scenes extras. The A/V quality is good but not super important, given that there are not a ton of special effects (other than de-aging Bob Newhart, who appears as Professor Proton). Overall, the show is well-written and very well-acted. While it is definitely a sitcom with a story-of-the-week flavor, it can also be considered a dramedy because it has very warm and heartfelt moments. Raegan Revord and Annie Potts steal every scene they are in. Revord really nails the character of Missy and makes you wish the character would have been around more in the parent series. Montana Jordan is also great as George Jr. and looks enough like Jerry O'Connell that you can buy that is who he will become. The show has pretty good continuity with BBT, other than the casting of Barber, who played a different role on BBT, but given that it was a small, one-off role, it is not really a big deal. If you are a fan of BBT, especially if you are a fan of the character of Sheldon, this is definitely a must-watch.