You can get some some halve good ones online these days... argos do some good laptops if thats what you and your lad wants.. Windows 8 to 8.1 is pretty standard these days.. with 4gb ram, god size Hard drive is about 500gig to 1TB
Graphics on them these days are pretty good.. I have a ASUS laptop. wife has a lenovo one which I brought her last year.. i was say 250-395 is a good going rate for laptops.. if you want a TOWER or DESKTOP Case.. i.e what I call a Family PC .. then try have a look in your local newpaper.. can pick some good ones for cheap as chips.. but still be pretty good value for money...
as the Inlaws brought a tower unit, monitor etc .. for just over £150 .. its a Beast of a PC .. So jelous wish i had seen before them .,.