Tips for Boot Campers
If you want your XP to look more like a Mac, the contest winner appears to be FlyakiteOSX. Making it work like a Mac is a bit different. You know, Home is My Documents and so on, and each platform is totally different under the hood, yada yada. More important is to just understand the difference between the two and deal with it. Unfortunately, there aren't a lot of data points out there for switching from a Mac to a PC. Statistically that's just not a big pool to draw from... There's a mostly useless CNet article from 2002. And there's a much better piece from Rolf Howarth in 2004. Rolf made the switch to XP and documented the affair. Skip through the hardware issues to the software bits though. Again, it's a little out of date (XP handles wireless pretty well nowadays, in my experience)... Oh and Jeremy Zawodny switched to a PC laptop last year and appears to enjoy it. Anyway, there are lots of differences. Mostly it's a change of geography, with the need for some extra security thrown in. Instead of the menu bar up top, it's the tray down below.
If you're feeling homesick for something like Quicksilver, we've had this discussion a lot on Download Squad, plus other modifications. Choose your poison. If you want to enable Microsoft's version of Fast User Switching, you can. Downloading the Google Pack is helpful, as you get a Spotlight-esque search tool and a task switcher. Gnosis has a ton of XP resource links for you to peruse as well, which range from troubleshooting to massaging more performance out of the OS. One idea to feel at home in either OS is to use nothing but cross-platform, open source apps. It's an idea anyway.
Hey, it could be worse. Try switching from UNIX to Windows.