I am a c# developer and most of my friends are much smarter than me, and they laugh at me and start to swear at me in smalltalk. I want to learn this so that I might better be insulted at their insults... and maybe learn a thing or two in the process.
So, what is the best place to start with regard to smalltalk in a windows environment?
The best current free Smalltalk is probably Squeak. This currently out-performs its near relative Pharo, at least on my ancient box, but you should really take a look at both of them.
The big problem with Smalltalk is that there are no really high-quality text books. There's a list of free ones here, but I couldn't recommend any of them strongly. If you decide to use Squeak, take a look at Squeak By Example, which isn't too bad.