They are both vary similar. The main difference is the size and shape. The DTR-T2100 is more compact.

Functionally they are almost equivalent and have the same menus. With the DTR-T2100 being more compact physically.

Catch-up services wise, the were the same a year ago (despite one sources announcement that Catchup was ceasing for the DTR-2000 on 28th February 2024) they are virtually the same.

The DTR-T2100 may have had some very small tweaks to its youview software than the DTR-T2000, but nothing that would be major.

The DTR-T2100 is BT badged box (as it was commissioned by BT), and the DTR-T2000 is a plan retail box. However both will respond to being used on a BT internet connection the same as each other. And both will respond to a non-BT internet connection the same.

Both of their remotes do have the same buttons, but in a different arrangement. A remote for one will work on the other.

The DTR-T2100 started out with a far superior remote, better layout – appeared to last longer before wearing out. Unfortunately later manufactured DTR-T2100 units came with what looked superficially the same as its original, but the remote is topographically different and can easily result in the wrong button being pressed for some of the buttons.