I have Office/Excel 2003 on Win XP SP3.

I would like to install (just) Excel 2007 (not Office 2007) on the same
computer (standalone laptop).

I have found a 2008 posting with a reference to an MS KB that suggests this
is possible as long as 2007 products are installed after 2003 products,
which would obviously be the case for me.

But that is not always the complete story.

Also, I am not an expert with Win XP and Office installations. I only get
them pre-installed on new computers that I purchase. So I want to be sure
that if I can install just Excel 2007 on the same computer with Office/Excel
2003, it is virtually turn-key and idiot-proof.

Can anyone share their personal experiences with doing what I want to do?

Any gotchas that I need to be aware of?

(Besides being sure that I don't use the default path when installing Excel
2007.)

Do Excel 2003 and 2007 share Registry keys?

Will IE6 continue to use Excel 2003, for example when I download CSV data
from an online bank account?

Will Win XP continue to use Excel 2003 when I click on a ".csv" and ".xls"
file?

Will installing Excel 2007 after 2003 impact the VBA that I access when I
press alt+F11 in Excel 2003?

Will some VBA (same or different) be available when I press alt+F11 in Excel
2007 if I install only Excel 2007?

(I don't know if VBA is integrated with Excel code, or if it is installed
separately. I know that there is a separate VB product. I don't think I'm
asking about that.)

Will I be able to uninstall Excel 2007 without affecting Office/Excel 2003?
Are there any gotchas to be aware of?

(Please answer the last paragraph only if you have personal experience doing
so.)

I can deal with issues involving sharing files between Excel 2007 and Office
2003 products. That is not a problem for me. I will probably use Excel
2007 just for isolated experiments.

I am only concerned about system-wide issues that might arise -- things that
might break or work differently after installing (just) Excel 2007.

TIA.