If you want a cheap, small laptop that does everything a traditional laptop or desktop can do, then a netbook is a great buy. However, netbook hardware is rarely as powerful as a "proper" laptop (what do you expect for the price?), which means it's not ideal for playing processor-intensive games or doing serious work such as video editing.
As a general-purpose machine for lighter tasks, such as word processing and web browsing, though, it's perfectly adequate.
So here's the dilemma. Most netbooks ship with Windows, either XP or 7. It's a very powerful operating system. But for those light tasks, it's not necessary. It's more bloated than it needs to be, and full of features that you don't need. So the limited amount of processing power in your netbook spends a disproportionate amount of time servicing Windows, rather than running the apps that you want to use.
One solution is to replace Windows with an OS that's designed for use on netbooks. Google is shortly to launch such a product, called Chrome OS, but it's not been released yet. In the mean time, there are 2 others worth looking at.
In both cases, there's no need to completely wipe Windows from your hard disk and replace it with Linux. Jolicloud can co-exist with Windows, offering you a choice at boot time. UNE can be installed to, and booted from, a USB stick, so you can experience it for yourself before committing to a complete installation.
But in either case, remember that replacing the operating system on your computer is non-trivial so don't be tempted to do it unless you're confident of being able to deal with any problems that arise. Having another PC to hand, so you can search the web for help if things go wrong, is extremely helpful. And make sure you've got a complete backup of all your important data. Plus, just in case you need to reinstall Windows, ensure that you have the relevant recovery disk to hand.
Also, operating system downloads are rarely small, and Linux is no exception. Both of the above-mentioned products run into hundreds of megabytes, despite the fact that the initial Jolicloud installer is only 16 MB (it will then begin a 2-hour download!).
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