I rarely use windows, and am a linux advocate, but Windows does allow a pseudo fork by creating a thread. The fork command will work on Window's versions of Perl, but there is hidden OS-specific magic.

The differences which I hassle with the most, is the line endings are different, requiring frequent dos2unix or unix2dos conversions. There is no easy to use IPC on pipes in Windows, so frequently used modules on linux, need special Win32 modules, like IPC::Run instead of the standard IPC::Open3. Also, Windows is done within the confines of a graphical GUI, wheras on linux, there is a true console, so you need to run wperl to suppress windows from opening. Finally, and the BIGGEST problem, there is the hassle of getting precompiled modules for the various versions of win32. Since you don't get an easy to use or install compiler with Windows, you need to rely on others to make many of the modules for you, and often they are hard to find. Wheras on Linux, the instructions to build modules generally work flawlessly.

To be honest, Perl was designed to run on Linux and Unix platforms, and if you want the most satisfaction from Perl, run it on Linux. Ubuntu is easy and the most Windows-like.... but I prefer Slackware, as it still adheres to the original simple unix style. But if you can't afford 100 hours to learn basic unix, then Ubuntu is great...it has the apt-get program to get you automatic updates, will connect to wireless access points automatically, and is supported for 5 years on each new release.