CHM2Word 2.0 Build 0315
with CHM2Word you can convert CHM files(help files) to microsoft word and edit topics with microsoft word
CHM2Word Features :

Drag and Drop supported to convert a CHM file to Microsoft Word Document.

Build-in Word Editor to edit and print the Microsoft Word Document directly.

Build-in simple HTML Editor to edit the HTML file directly.

CHM Decompile function supported.

Microsoft Office XP Style and Microsoft Office 2003 Style theme supported.
below you can download CHM2Word 2.0 Build 0315
http://www.dawningsoft.com/downloads/chm2word_setup.exe

From reading several articles on CHM, it looks like that compiled help files are now being depreciated and are being replaced with Microsoft Assistance Markup Language files. I think that Windows Vista cannot open CHM files because the help program was not included.

Also, from reading http://en.wikipedia.org/wiki/Microsoft_Compiled_HTML_Help, it shows that you can extract CHM files by using certain Windows, Max and Linux tools, without third-party software like the one you mentioned. I think that I would do this rather than download software to convert from a proprietary file format to another proprietary file format.