How to change the default location of 'Music', 'Pictures', etc. in my home folder?

[Mic'sBook]

IMAGINE I have 2 hard disk partitions on the SAME hard disk,
one is called 'Macintosh HD' and the other is called 'My Data'.

The Plan:
In the 'Macintosh HD', there are (1) system files & (2) users' settings.
In the 'My Data', there are all the music, pictures, etc.

For example, the 'Macintosh HD' has 40GB and the 'My Data' has 120GB.
All I want to do is to separate the SYSTEM and my DATA without migrating my home folder inside 'Macintosh HD' which contains folders called 'Music', 'Pictures'... to the partition 'My Data'.

I want to separate the system files and my data incase I need to reinstall the Mac OS X while leaving all my data untouched.

So the way I should do (I guess) is to leave my home folder inside 'Macintosh HD' empty,
and create files called, for example, 'My Music', 'My Pictures', etc. in the 'My Data' partition.
Then redirect the files 'Music', 'Pictures', etc. in my home folder inside 'Macintosh HD' to 'My Music', 'My Pictures', etc. in the 'My Data' partition.

In Windows XP or Windows 7, you can redirect those as using the methods below:
(1) http://i41.tinypic.com/2rorkhx.jpg
(2) http://www.sevenforums.com/tutorials/18629-user-folders-change-default-location.html

But I just don't know how to do that in Mac OS X, it seems that Mac OS X doesn't even provide a way for users to do so:
http://forums.macrumors.com/showthread.php?t=336192

I saw a reply in macrumors forum and tried to move the 'Music', 'Pictures', etc. folders,
but it turned out that those files were being copied, not moved.
So I can't move the 'Music', 'Pictures', etc. to the partition 'My Data' and make aliases of them which can be put in my home folder inside 'Macintosh HD'.

So, are there only 3 options for me too choose?
(1) stop trying to fight Apple and Mac OS X on where it puts things, just put all the things in my home folder inside 'Macintosh HD', using only 1 partition
(2) move my home folder to the other disk partition, in this case, the partition 'My Data'
(3) can't redirect the location of Music', 'Pictures', etc. folders in my home folder in the 'Macintosh HD', but just simply put things in the 'My Data'.

Thanks in advance!

 

[spinnerlys]

If it comes to the case of re-installing the OS, you get the option (pre 10.6) of doing an Archive and Install, which puts all the data on that HDD into one folder, which you can easily access at a later time.

With 10.6 you just re-install the OS, all your data stays untouched.

If you need to format your HDD, it's best to get an external HDD and clone all your data on it.

There is really no need to partition the HDD as it is with Windows, I made that discovery myself a long time ago.

If you use MRoogle though you might be able to find relevant information.

 

[NorCalLights]

Aliases won't work. You need to create symbolic links (which are like aliases, but the filesystem can't tell the difference between symbolic links and the actual folders). Here is more info (and google has tons more): http://www.macosxhints.com/article.php?story=2001110610290643

1. Move the folders to your external hard drive.
2. Create symbolic links to the folders in their new locations, and place these symbolic links in your home folder.

 

[Mic'sBook]

If it comes to the case of re-installing the OS, you get the option (pre 10.6) of doing an Archive and Install, which puts all the data on that HDD into one folder, which you can easily access at a later time.

With 10.6 you just re-install the OS, all your data stays untouched.

If you need to format your HDD, it's best to get an external HDD and clone all your data on it.

There is really no need to partition the HDD as it is with Windows, I made that discovery myself a long time ago.

If you use MRoogle though you might be able to find relevant information.

Aliases won't work. You need to create symbolic links (which are like aliases, but the filesystem can't tell the difference between symbolic links and the actual folders). Here is more info (and google has tons more): http://www.macosxhints.com/article.php?story=2001110610290643

1. Move the folders to your external hard drive.
2. Create symbolic links to the folders in their new locations, and place these symbolic links in your home folder.

Thank you spinnerlys & NorCalLights!
Lesson learned: symbolic links

It seems that I'd better stop trying to fight Apple and Mac OS X on where it puts things,
as Time Machine / Carbon Copy Cloner / Disk Utility are good ways for backing up files.
Just spend more time doing what I want rather than configuring the computer!