Install Excell 2000 on a system running excel 2007

I am running Excel 2007 on my Windows Vista laptop. A workbook I've developed in Excel 2007 (compatibility mode) on my Windows Vista laptop has a macro that runs as expected on my laptop but will not run on my desktop which is running Windows 2000, Excel 2000.

I've addressed this question previously under the thread "Macro Bombs Excel 2000". I've not received a response as to why it won't run under Windows 2000, Excel 2000. I don't know if it's an Operating System issue or an Excel 2000 issue.

I'm developing this workbook for my children for their personal financial management. I'd like to determine if this is an Excel 2000 issue or an Operating System issue. Most of my children run Windows XP, Office 2000. I have a dual system on my laptop (Vista and XP).

I have a legal software license available for Office 2000. My question is, can I load Excel 2000 on my Vista, Office 2007 laptop. I've looked at http://support.microsoft.com/kb/218861/ and they talk about installing oldest versions first. I have Excel 2007 already installed. I don't particularly want to uninstall it. Can I install Excel 2000 without uninstalling Excel 2007?

1. Can it be done?
2. Can it be done without MAJOR operational issues.
3. What is the process?
4. Can I load ONLY Excel 2000?

Your help is greatly appreciated.

John