Dual boot on xp-hidden folders?

hi all :)
i'm running xp pro, i've 3 partitions on my 500G HD
c-xp physical drive
d-empty
e-backup
i'd like to install win7 on "d" partition.
i read the excellent dual boot tutorial
Dual Boot Installation with Windows 7 and XP
now,on my computer i see 2 hidden folders both on d and e partitions
1-System Volume Information (empty)
2-RECYCLER (empty)
i can not delete them, and system restore is turned off for d and e partitions.
My questions are
*can/how to delete those files?
**those files will interfere with win7 instillation on "d"?
thanks!

The folders need to be there.

thanks theog.

so when i'll install win7 on "d" , will the instillation creates another pair( of 2) hidden folders to each partition as well(this means i'll have 4 hidden folder on each partition)?

No, overwrite the folders.

thanks again,

No, overwrite the folders

theog, are you writing from your own experience/similar situation?

after finishing installing win7- will i have 2 system separate BIOS's ( xp-win7)?

All PC's only have one BIOS.

thank you!

Another question :

I will install Windows 7 on another partition, what about SATA CONTROLLER? the installed XP SATA CONTROLLER Is on the IDE so it means that windows 7 will be on the IDE? or replaced to AHCI?
After all, there is only one BIOS, what do you think?