multi volume LVM

I am having trouble using LVM on a xps 720 with two 250GB drives and firmware raid 0. There are two issues here, one is what I will explain below and the second is Ubuntu, unlike Windows, Fedora, OpenSuse does not honor the firmware raid 0. In order to get the installed system to boot I have to disable firmware raid on both drives. That shouldn't be required as not only Windows honors it but so do other Linux distros. OK, on to the other problem.

Here is a pvscan and lvdisplay:

walt@cor720:~$ sudo lvm pvscan
PV /dev/sda5 VG cor720 lvm2 [232.59 GB / 0 free]
PV /dev/sdb1 VG cor720 lvm2 [232.83 GB / 0 free]
Total: 2 [465.42 GB] / in use: 2 [465.42 GB] / in no VG: 0 [0 ]
walt@cor720:~$ sudo lvm lvdisplay
--- Logical volume ---
LV Name /dev/cor720/root
VG Name cor720
LV UUID g2Jod5-ZqxW-U5Ju-TS7B-QJG5-yIUP-v68cJJ
LV Write Access read/write
LV Status available
# open 1
LV Size 456.56 GB
Current LE 116880
Segments 2
Allocation inherit
Read ahead sectors 0
Block device 254:0

--- Logical volume ---
LV Name /dev/cor720/swap_1
VG Name cor720
LV UUID uMXrIl-dDqS-VLrz-VzuL-u2T3-4Ybf-PqMggF
LV Write Access read/write
LV Status available
# open 2
LV Size 8.86 GB
Current LE 2267
Segments 1
Allocation inherit
Read ahead sectors 0
Block device 254:1

That looks pretty good, right? Says I have two 250GB physical volumes and one logical volume (well 2 counting swap) and that the 465GB LV has two segments, presumably the 2 PV's. HOWEVER
walt@cor720:~$ sudo fdisk -l

Disk /dev/sda: 250.0 GB, 250000000000 bytes
255 heads, 63 sectors/track, 30394 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x561ee893

Device Boot Start End Blocks Id System
/dev/sda1 * 1 31 248976 83 Linux
/dev/sda2 32 30394 243890797+ 5 Extended
/dev/sda5 32 30394 243890766 8e Linux LVM

Disk /dev/sdb: 250.0 GB, 250000000000 bytes
255 heads, 63 sectors/track, 30394 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x000a92d9

Device Boot Start End Blocks Id System
/dev/sdb1 1 30394 244139773+ 8e Linux LVM

walt@cor720:~$ df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/mapper/cor720-root
232754316 178490704 42533488 81% /

You can see from the df that it shows only the first drive (232GB). The available is counting mounted nfs drives. I do not understand why when lvm is happy I have 465+GB from the two drives, well presumably from the two drives, the disk system shows only the first. Now the fstab the install created follows, if that is any hint.
proc /proc proc defaults 0 0
# /dev/mapper/cor720-root
UUID=1484d5c4-baa1-4520-a443-de92282cb1f9 / ext3 relatime,errors=remount-ro 0 1

Further down it has the mount for the swap LV.Notice though the UUID of the /dev/mapper/cor720-root and the uuid from the lvdisplay. They differ. I tried specifying that UUID and got 222GB.

To get this far required much manual intervention in defining the volumes as LVM and once booted, adding the second PV into the main LV. This confuses me as with other distros (Fedora 8, in my case and I understand OpenSuse does as well) once the installation is complete there is a single LV that spans the volumes.
So, OK, I had to update the LV manually, the installation does not recognize or does not seem to recognize the LV.

Any assistance on this will be appreciated.

Thanks,
Walt