Location of ADOBE products

C: OS and programs
D: Media
E: Scratch drive
F: Audio preview
G: Video projects
H: Other material

These are physical drives, not partitions!!!!

The applications themselves should really be left to install into the default
folders that appear in the install dialogue.
This way, all the integration will work correctly, and any updates can be
correctly installed as well.
However, when it comes to your actual projects, the way I work is like this:
C - Operating System (Windows XP) and Applications
D - Audio Work Drive
E - Samples
F - DVD Authoring Drive (Contains all DVD Projects)
G & H - Burners
I & J - External HDD for backups & images
V - Video drive, for Uncompressed Video files.

You won't need to go quite this far.
What I would definitely recommend is a dedicated, second HDD for your Adobe
Projects though. Look for a spin speed of 7200, with a 16Mb Buffer for
preference (although an 8Mb will do - just) and the fastest seek time &
sustained data transfer rate you can find. Data transfer rates are actually more
important than spin speed.

Don't make this by partitioning your C drive though, as this will reduce
performance as you are literally trying to tell the read/write heads of your HDD
to be in 2 places at once.

Don't worry about RAID - odds are you just do not need it at all, and it can get
very complex to set up in such a way that you are actually safe - despite the
marketing, RAID 5 is the *only* configuration that both improves performance and
creates safe backups. Avoid for now unless you are into some heavy HD Video
editing.
Don't worry too much about SATA or SATA 2 either. EIDE is just as good and
cheaper.
What matters is a decent performance separate HDD for all your projects.

      RAID 5 is the *only* configuration that both improves performance and
      creates safe backups.

      Don't worry too much about SATA or SATA 2 either. EIDE is just as good
      and cheaper.