Reasons (only personal view):
(1) Faster and new processor, not easy to upgrade if you want to, so better to get faster one
(2) Big HDD, can be easily upgrded, but extra cost.
(3) Most important one: Good graphics (ATI Mobility Radeon 9700 128MB), excellent for game. For a laptop, this is something you CANNOT update.
(4) The weight of ToysRUs one is too heavy (3.2kg) for a centrio laptop, do not the weight of Aldi one
As for Wireless Router/Modem, you can get a better one at low costs, e.g.
D-Link 54mbps DSL-G604T Wireless ADSL 4 Port Modem Router £65.06 click here