First of all thanks for all the advice. I had decided on some form of windows based netbook as I have a variety of windows based programs for flight planning and GPS updating which I need to use as well as browsing the net. If I could be sure the apps would work on a Linux system with an “emulator” then I would be happy with this. If the stuff does not work or I have to spend days struggling then it would be a big mistake. How big is the risk?
Rod1
Easiest life, if you want to run Win stuff, is to buy a laptop than runs windows natively. Buying a linux machine, and installing WinXP might fail if you can't get the drivers you need for your hardware. If you buy a Win laptop, pretty much everything will run out of the box. It may run slowly, it may be insecure, but it will all run and you'll find (fairly expensive) support for it at your local pc world.
If you don't mind fiddling with your machine and want something more reliable then buy a linux machine and run your apps through wine, or through a VM.