Stripe set question

This is an additional question related to the
previous "Dynamic disk vs. RAID" thread.

Is it possible to put in a single stripe set:
one partition from a disk that contains two partitions,
together with the single partition from a second disk
(both partitions having the same size of course)
Let me explain more in details:

I have a computer with the following setup:

IDE Channel 1, master = 80 GB original hard disk
IDE Channel 1, slave = 40 GB added hard disk
IDE Channel 2, master = DVD-ROM
IDE Channel 2, slave = CD-RW

both hard disks are Maxtor 7200 RPM with very similar
performance (except the size)

also via an added firewire card, I have an external
DVD+RW and a 200 GB external HDD.

Currently, my hard disks are configured as follows:
IDE disk 1, partition 1 (40 GB): OS & apps
IDE disk 1, partition 2 (40 GB): DV data, secondary
storage
IDE disk 2, partition 1 (40 GB): DV data, primary storage

I am considering slightly improving performance and
unifying DV storage space by doing as follows, without
purchasing any additional hardware:

disk 1, part1 (40 GB): OS & apps (no change)
disk 1, part2 + disk 2 (40 + 40 GB) = 1 stripe set (80 GB)

In order for the software stripe set to perform
optimally, I understand it best then to move the 2nd HD
to the IDE channel 2 (avoid the 2 HDs on the same
channel, to improve the concurrent I/O) ?
But I read posts elsewhere recommending against mixing
HDs and optical drives on the same channel ?

Burning CDs isn't what I want to optimize (I can still
use the firewire DVD+RW drive for that), so I think the
following config isn't bad:

IDE Channel 1, master = 80 GB original disk
IDE Channel 2, slave = DVD-ROM
IDE Channel 1, master = 40 GB added disk
IDE Channel 2, slave = CD-RW

I do understand RAID0 does not provide any protection
against disk failures


Also, if I keep the two HDs on the *same* IDE channel,
would the performance gain of the stripe set still be
significantly better than no stripe, IOW, how much
additional perf does alternating the channels buy me ?

thanks