Stray Kittycat

I am thinking of buying a new computer in September and wanted to know the differences in the different chip sets and what they could do compared to each other. I intend to get a good graphics card as well as this computer will be mostly used for a mmorpg... City of Heroes. I`m not particularly computer-literate so a layperson`s explanation would be appreciated.

I see internet promotions all the time on American sites offering a laptop or computer to test at home but are there any in Canada that do this? Or are these freebie promotions just a scam to get your web address to inundate you with spam.