I've 'validated' that my webpage (website) works ok on IE6 and Firefox (I have both installed on my PC), but I want to verify on IE7 also (especially now that IE7 is officially released). This isn't strictly an HTML/CSS question, but does anyone know if I can run all three browsers on my PC ... Win XP, SP2?

It's not so complicated. You have to install standalone versions of IE

Read:
http://www.tech-recipes.com/internet..._tips1188.html for IE6 and IE7
http://www.quirksmode.org/browsers/multipleie.html. (only IE <6)

I haven't tested the IE6 and IE7 but I used to test IE6, IE 5.5 and IE 5.01 and once and it was possible.

Thank you