Hi.
I actually live in Ilford and work in the city, and I have a different perspective from the other posters who have answered you. Ilford is, in fact very well located for travelling to central London if you were looking to strike a balance between accommodation cost and convenience. Ilford (actually in Essex) is a late 19th century suburb, with many large (by London standards) houses although many are now divided into flats. It has many large shops and is very multicultural - so it's not a chi-chi suburb! It also houses many commuters. I can't vouch for your particular hotel in Coventry Rd, as to my knowledge there are none of the big chains there, but it is close to Ilford Station. Note though that it is a long road by local standards, so if your hotel is at one end it is only 4 minutes walk to Ilford Station - it will be almost 15 mins from the far end.
By train (direct from Ilford to London Liverpool St Stn) it is only about 20-30 mins max, and £7.60 return in the rush hour. From Liverpool St you can walk round the City of London from the door - the Thames and Tower of London are a scenic city 15 minute walk. Also from Liverpool St you can catch Underground services - central line in to the West End; Metropolitan line or Circle Line to areas like Kings Cross, Regents Park, Baker St and clockwise round to Embankment and Victoria - all of these places are about 15 to 25 mins additional travel time. Put another way, you can access anywhere in central London in an hour from Ilford.
To get from St. Pancras to Ilford, follow the signs for the Circle line (underground) at St. Pancras. Get on an eastbound train and get off at Liverpool St. Go up to the main surface level terminus, and to find the Ilford trains walk towards Platform 16 or 17 - look at destination boards (at the platform gates) for trains to 'Shenfield', checking that the particular train stops at Ilford (most do but not all). Its only 4 stops on the Circle Line to Liverpool St, and only 5 stops rom Liverpool St to Ilford. Don't foget to ensure you get a ticket at St Pancras/Kings Cross that allows you through to Ilford - Ilford has ticket barriers. Enjoy!