I have been trying to get to Safe Mode to solve some problems and had major difficulties getting to it. Most forums and posts say press "f8" on startup (which is the normal Windows option). This did not work.
I discovered that pressing "f2" IMMEDIATELY (literally a split second) after Windows begins to start - for me this was after my Boot security key was entered as I have a HDD encryption system, but would otherwise be just after the Toshiba page which offers the option of f2 or f12 closes, that you get to the page which offers you the option of pressing "f8" to get to the startup options page.
I hope this helps someone and prevents the frustration I had!