Hi Ewan,

just like you I had been looking for a way to combine both Windows and Linux. Here is my solution:
- On my desktop computer (AMD Sempron 3100+, 512 MB RAM, 80 GB hard disk) I installed Windows XP and VMWare Workstation for Windows, a non-free program similar to Microsoft's Virtual PC. Within VMWare Workstation, I can have as many virtual Linux installs as I like, and switching between Windows and Knoppix only takes a second. VMWare offers a 30 thirty day evaluation version, so you may want to test it on your PC.
- As a backup solution, I bought an older Pentium III notebook on eBay that I set up to do a "traditional" dual boot.

Conversely, it also possible to run Windows from within VMWare Workstation for Linux, but I haven't tried it yet.

I hope you'll find my comments helpful.