I had used it before but I see what you mean!
It's the videos that it has selected to show from "Featured Videos" "Most Discussed" etc (or whichever category you browse!). They do appear to all be Russian but if you search for something in English you will get English results.
It's not that the titles appear in Russian, it's that the videos given to you are Russian. No idea how to change that though. There doesn't appear to be any localisation setting... maybe there is an option on the YouTube website to set a location for your account??