Advantages of the Windows / Intel (Wintel) platform:
You can get a computer very cheaply, if price is your primary concern. However, when comparing features, make sure you pay attention to what is built in. Macs are price-competitive with name-brand PCs with identical features. Make sure you pick a company that will be around when it comes time to make a warranty claim.
You can custom-build a computer to your exact specifications, if you have very specific hardware needs. However, for most people and for most day-to-day tasks, any current computer (Mac or PC) will be plenty fast for word processing, web browsing, email, playing music, burning CDs and so forth.
You can get very cheap software. However, if the software is low-quality, you lose money on efficiency in the long run. How much is your time worth?