if your of a mind to pay someone let them do it from the start.
If you give them the machine without you fannying around with it, its a relatively simple job. Once you have half screwed it, it will take twice as long and mucho frustration to fix.
Don't go to PC world they will feed you some bollocks.
You want current disk cloned to a larger disk 500mb or 750mb will do fine.
Windows 7 or 8 installed as a dual boot with XP.
XP rendered safe by removing hardware drivers for the networking.