W7 and XP and advanced options

I am dual booting W7 and XP, with W7 as the default after 20 seconds. I can set advanced options for W7 but the option is not available for XP (options in gray, can't check box). Is there a way that I can have the option at bootup to go into advance options for XP with the F8 key similar to W7

Select XP from the bootmgr menu
Then tap F8 repeatedly.
F8 is an interrupt.
If you tap it at the start you are interrupting the W7 bootmgr and you'll get the W7 extended menu.
You must wait until W7 bootmgr chains to XP's NTLDR then hit F8.
That way you interrupt NTLDR, and it will display the XP extended boot menu.