If you want to play games you can forget about all that MAC nonsense!

Five hundred pounds is pretty low for playing high-end games like Crysis which has a reputation for eating computers up and spitting them out. You might find one that you could play it on at a lower resolution.

For the most computer for the price you probably need to go to a brand-name computer like Dell, that has a plant in your country (England?) so that it doesn't have to get shipped across the ocean.

Your big cities probably have stores like Best Buy that sell computers, don't they? There you can see what you are getting for your money. If you live far from a city, then save up more money and wait until your next holiday to buy a computer.

Macs have better resale, are easier to use, make better (more efficient) use of the hardware, are more reliable, are more secure and their total cost of operation is lower than PCs.

PCs are cheaper, initially, than Macs. There are lot of people out there who know Windows so its easy to to find someone to comiserate with.

I have found noone with real experience in both platforms that prefers to use Windows for their desktop. Even if you're just going to use the machine for surfing the Internet, Windows and Internet Explorer are notorious for their security holes. The MacOS os layer (based on FreeBSD) is far far more securely written so it is harder to write viri for (and obviously, since Macs are a smaller part of the market, fewer people are writing viri for them to begin with).

In particular, once you understand generally how Macs do things, you can pick up new applications very easily. There is far more (needless) variation in how interfaces work across the Windows platform, so applications take longer to master.

The vast majority of large commercial software products out there have Mac versions, and its relatively easy to run either a virtual machine or "boot camp" (dual boot) if you must run Windows products on your Mac.

I have given members of my family Macs because I don't want to be their system administrator if I can help it. They can administer their own machines. If I had given them Windows, I basically would have been signing up for a no salaried system admin for as long as they had my gifts.