Ed, come back! Stop head kid getting in to this computer (7)
I believe the answer is:
desktop
'this computer' is the definition.
(desktop computer is a kind of computer)
'ed come back stop head kid getting in' is the wordplay.
'come back' says the letters should be written in reverse.
'head' suggests taking the first letters.
'getting in' means one lot of letters goes inside another.
The initial letter of 'kid' is 'k'.
'ed' in reverse letter order is 'de'.
'stop' enclosing 'k' is 'sktop'.
'de'+'sktop'='DESKTOP'
'to' acts as a link.
(Other definitions for desktop that I've seen before include "board?" , "Background in computing" , "working area in office" , "Location of icons" , "Main working area of PC" .)