Happy 99 is although very annoying actually a very friendly virus...The writer obviously wanted to propagate his work around the world and make things very easy for people to see what he has done. Egotistical, you bet...
Removal is dead simple.
First reboot your system into "dos safe mode" then follow the instructions below. You could even write a smal batch file to do this automatically should you for what ever reason wish to watch the fireworks again.
C:
CD\
cd windows\system
del wsock32.dll
ren wsock32.ska wsock32.dll
del *.ska
Reboot and your system is clean again.
The happy99.exe is harmless as long as you don't run it.
Whooaahh!!