Disk Management

Hi, I have four hard drives. Three internal and one external. I have set up two bootable hard drives and one backup hard drive with two partitions. I have a boot manager installed so i can boot from either windows 7 or windows xp. My question is about partitions. I'm not sure how many types of partitions there are, however i heard of four, Active, Primary, Extended and Logical. I would like to know if I set up the drives and partitions correctly. this is my setup:

Disk 0 - Windows XP (M 149GB NTFS
Healthy (Active, Primary Partition)

Disk 1 - System Reserved 100 MB NTFS
Healthy (System, Active, Primary Partition)
Disk 1 - Windows 7 (C 931 GB NTFS
Healthy (Boot, Page File, Crash Dump, Primary Partition)

Disk 2 - Backup 1 (D 465 GB NTFS
Healthy (Primary Partition)
Disk 2 - Backup 2 (F 466 GB NTFS
Healthy (Primary Partition)

And an external Hard Drive:

Disk 7 - New Volume (E 232 GB NTFS
Healthy (Primary Partition)


Please let me know if this setup is right. I do not know when to mark a partition as active, or when ti use extended and logical partitions. Any information you can provide will be appreciated. Thank You