hi all i just read this entire thread (bored) and i would like to throw a few suggestions out there.
1. Assuming that lanschool installs in the program files directory, can you just delete the .exe or some of the dlls it needs and just have it crash when it starts. or even better, just delete the whole freaking install folder of that thing.
However to do this you'd probably need admin rights. one way would be to just boot into a distro(backtrack or even dos) cd into sdb1 or whatever is equivalent of C:\ProgramFiles\Lanschool(or watever its folder is) and just delete the contents or the whole folder. Or: Last year i discovered that you could right click a file and click open with and then click browse from the dialog box that opens up you can delete contents of program files. However this may or may not working depending on the permissions and tweaks ur it ppl have implemented. Also, this allows you to go to sometimes restricted places such as my computer from where you can go to network and so on ....
deleting some files will just probably render it as broken leaving nothing that would show that it has been uninstalled as it will probably still show up in add and remove programs ..