The Online Family answers:

For starters, take inventory of how everyone in your family uses the computer now, and what capabilities they'd like in the future. For example, if your kids mostly need to use the computer at home to print school reports, then they probably don't need the mobility offered by a laptop. But if the adults in your family would like to be able to follow a recipe via a computer while in the kitchen, or maybe get some work done in a quiet corner of the house or local caf‚, then consider a laptop. The good news is that a laptop can be hooked up to a regular computer monitor or keyboard so it can function just like a desktop. The bad news is that feature-for-feature, laptops still tend to cost more than desktops and are much easier to steal, lose or damage.