Just had a look at your hotel, looks good for the price, area is good and plenty to do, eat and drink near by.
I regularly walk from Euston to Tottenham court road in about 12 mins to give you a sense of distance and time.
On days out with the mrs we like to walk London. You do get lost from time to time but plenty of hidden gems. 1 day we will walk from primrose hill, through regents park, through the centre of London and down to Chinatown and eat. Then walk along the embankment after before heading home.
Next day we might walk from Kensington, through green park, st James park and wonder round Buckingham palace and take the back streets, Westminster and then catch the train to the Tate. Have a wonder around there, over to St. Paul's, get a pizza at pizza express. It's a nice few days wondering around London.