Yes. I use it all the time. Just press Menu, Search and Browse, and then On Demand. While in search and browse, I usually enter the keywords for content titles and then go on demand.
Just to clarify. DTV is not Netflix. You don't stream content off the internet like you would on Netflix. You download it. However, once a download has started you can start watching it immediately if your internet connection is not too slow that is. DTV's "on demand" really means instant access. DTV's Cinema on demand is often available in 1080p too. Using VOD or video on demand I can download TV series episodes, premium channel shows, sports events, and movies right to my HR24 receiver's hard drive and view them whenever I want. However, don't wait too long. Most d/l programs, not all, will have an expiration date, usually within a couple of weeks to a month. The PQ on DTV is superior to Netflix too. I have never experienced drop outs or time outs using DTV's on demand, but I do have a 12 Mbps broadband connection.
There is a caveat however. If your internet connection is really slow say below 3 Mbps, it could take perhaps a couple of hours and longer to download movies. When I had 3 Mbps broadband after I first got started with DTV, it took just over 4 hours to download Seven Years in Tibet off ShowTime VOD in 1080p and 5.1 surround sound. So, the faster your internet connection the better.