Windows to Macintosh
In migrating from Windows to Mac, most of the experience is positive. Printers just work when you plug them in, etc. However, there are some annoyances, where the Mac just doesn't work as well as Windows.
For migration -- and especially if you have to use Windows still sometimes -- it is best to keep the control key. To do this, go to Apple>System Preferences>Keyboard>Modifier Keys and switch the Control and Command.
To see the open windows, use F9 (for all) or F10 (current application). (In Windows, you'd look at the task bar at the bottom.)
Addresses. To migrate from Outlook is a pain.
On the web, the best advice I could find was on Windows: to download Thunderbird from mozilla.org, run, import addresses from Outlook, export to LDIF file, then copy to Mac. On Mac, import into Address book. That just doesn't work (the addresses get all screwed up)! Nor does it work with a CSV file into the Mac Address book.
What finally seemed to work was to take a CSV file exported from Outlook, on the Mac create a new GoogleMail account, import the CSV file into Contacts, then export a vCard file. You're asked to open with the Mac Address book. Do so, and it all seems to work.
Office documents. Download and install OpenOffice. Most stuff works, but sometimes the formatting is way off. Alternatively, on Windows import the documents into Google Documents; not as powerful, but accessible from any machine, and sharable. Open it up and import your Windows Office document.
You can't resize windows from any edge; it has to be the bottom right corner. You kinda get used to this over time, but it is still a pain; much less flexible than Windows.
You can't delete a file in the finder with the Delete key. Workaround: use Right-Click>Delete or use Command-Delete
Right-click on the mouse is called "Control-Click" in the documentation.
Double-clicking on a Dock item doesn't open a new window - it just brings windows to the front. Workaround: after double-clicking, use Ctrl-N.
Double-clicking on a window title has the reverse effect on windows and on the Mac. Workaround: click the little buttons instead.
It is a complete pain to use file names, like /Users/markdavis/Documents/pictures/IMG_9696.jpg
To get a file name from a file, you'd think that you just have to use Get Info, and then Copy. However, Get Info dialog inexplicably doesn't allow Command-C or Right-Click copying! (That appears to be a general failing on the Mac, that you can't copy text that you can see.)
Workaround: Open a Terminal Window. Drag the Finder item to the Terminal Window. Copy
To open a file from a name, there is a spiffy new mechanism. Make a new Finder Window, then Command/Shift-G, then paste in the file name. Then if the name is a folder, hit Go. Inexplicably, however, it won't open a file.
Workaround: Open a Terminal Window, type "open" paste the name, hit Return.