A couple of options would be the new Ren. at St. Pancras, it is a wonderful location if you plan to travel by tube or Eurostar. Likewise, another favorite is The Grosvenor Hotel, a wonderful experience as well. Shop for the best price, or point deal. Good luck, you will have a great time!
My daughter studied at Regents 2 years ago. A great experience...your daughter (and you) will love it!!! I stayed at the Renaissance St. Pancras, which has been recently restored to historical splendor. You can take the chunnel to Paris from the St. Pancras Station right beside the hotel. Old-world chic! Also, was a guest at the Chancery Court Renaissance located at the foot of the Westminster Bridge. This is a landmark building that has a spectacular view of Big Ben, Parliment, and West End London. My daughter and I would often meet at Trafalgar Square...a 30 minute entertaining stroll from Regent's Park for her, while it was a 20 minute promanade for me from Chancery Court. If we return, we would stay in the same properties ...Good luck with your search and hope you and your daughter enjoy London as much as we did!!!