People seem to easily miss the "Setting up build tools" section, so I
have moved that step above the filesystem information and linked
directly to BuildInstructions.md to hopefully make it harder to skip.
Also, added mention of `\\wsl$` since that regularly comes up in
Discord.
This is no longer relevant for most users because due to an
unrelated change to Meta/run.sh the default display backend is now
SDL which does not exhibit this problem.
The x86_64 QEMU binary supports both i386 as well as x86_64 guests.
By using the x86_64 binary users won't have to change anything when
switching between i386 and x86_64 builds.