You'll have better luck searching for "Ueno" instead, Taito-ku is a purely bureaucratic designation. I haven't stayed at the Sofitel, but I've walked past it many a time: it's a round mini-skyscraper right at the edge of Ueno Park, a famous cherry-blossom viewing spot (in the very brief season), the site of the Tokyo Zoo and a whole bunch of museums including the National Museum.
That said, it's a low-key working class district, the heart of "****amachi" as the Japanese say, and the Sofitel frankly seems a little out of place. There's good cheap shopping and eating but none of it particularly tourist-oriented (not that many things in Tokyo are). It's a bit of a slog to anywhere else, but Ueno is very well connected by the Yamanote railway, the Ginza subway line and the Keisei Skyliner straight to the airport, so you can get to pretty much anywhere in half an hour.