Following on from my recent move to Ubuntu, here are a few tips you might find useful if switching from XP/Vista to Ubuntu:
- use the Live CD to try Ubuntu out: download it, burn it, and run the ‘demo installation’. This lets you try out the operating system without actually installing it. For me it was a great peace of mind to find that the wifi & network settings just worked out of the box (and with access to the internet any potential problem could be fixed!)
- trust the dual boot steps: the Ubuntu installer does the job of partitioning your hard drive, I found the whole dual boot install process was incredibly straight forward. Although on reflection, given how little I need to boot back to windows (only a handful of times), a better option would of been to create a VM image of my windows machine (store it somewhere), not bothering with the dual boot setup (format the machine for Ubuntu only) and just use the VM image directly from Ubuntu if I ever needed to run Windows.
- use synaptic package manager to find and install applications: synaptic is a great tool (the ‘multiverse’ repository option found everything I needed), a comprehensive guide on using it (and other methods of installing software) can be found here.
- install ‘nvidia-settings‘ (if appropriate to your hardware obviously): took me some time to get the dual screen setup working until I stumbled across the nvidia-settings tool, which makes multiple monitor setup a breeze. Would of been nice if this was installed by default by the installer. (Use Synaptic to find and install nvidia-settings)
- finally, don’t let this happen (thank you xkcd!):

Cheers James. The Live CD’s are also a great way of trying out the various flavors of Ubuntu (e.g. Kubuntu: http://www.kubuntu.org/getkubuntu and Xubuntu: http://www.xubuntu.org/) to see which desktop system you prefer.
I have a really old laptop (from around 2001, which makes it about 60 in internet years!) that’s practically unusable as its so slow running XP, keep meaning to trying out Xubuntu on it and see if it gives it a second lease of life.
Good luck if you go ahead with the move.