How to boot to safe mode. F8 doesn't work!

Hi,

I have an Inspiron 1501 Laptop. It originally came with Windows Vista Home Premium but I've recently gone back to Windows XP SP2.

 

I wanted to go into Safe Mode yesterday but on boot-up, when I hit F8, nothing happened. I tried all the F keys on boot-up but the only ones that did anything were F2 (goes into BIOS) and F12 (I can select a one time boot device).

 

I thought F12 was it but Safe Mode wasn't in the menu so I'm at a loss.

 

Any ideas?