Everyone seems to be encouraging you to go for this deal, and to take the 50mm along with it. Im going to advise you try bargain with Mike and the boys. Try discount the overall price by going for this body, and the 55-250mm and try replace the 18-55mm with the 50mm.
The 18-55mm is a dog, and if you really feel youre missing out on the wide angle length buy a secondhand one on ODP for next to nothing, or buy a wide angle prime (which are also relatively cheap) at a later stage.
Either way, its a good deal, for the body and lenses. The body will last you a long time, if you look after it... The lenses you can accumulate later as you grow used to shooting with a slr.