in a need of a little help...

This is for a work project. I need to set up a Vehicle Dimensional database.
I'm in need of some ideas. Requirements are the data content will be served and we would like a web interface using IE. Output formats will include MSExcel 2007. Oracle, MSAccess and MySQL are, unfortunely, out of the question. So, I was thinking about using XML for the data content and maybe PHP for the application code? Then XHTML for the web interface?

I'm looking for any ideas from any one with previous experience in a similar situtaion.

Also, any ideas on how to handle the data tables in XML format.
With vehicles, we have the year, brand, model, body style, energy source, and the four possible dimension types. For example, 2007 Toyota Camry, 2-door coupe/4-dour sedan, hybrid, and for dimensions will include Lenghts, Heights, Wides, Angles, such as Vehicle Overall Lenght (OAL), Overall Height (OAH), Overall Wide (OAW). We will want to filter by year, brand, body style, energy source. For example, one filter may be get me all 2008 4-door sedans that use gasoline only. Or get me all 2005-2010 Toyota hybirds.

Any help would be greatly appreciated.

I not asking for written code, just get me going in the right direction with the correct tools to use and any other ideas, so I can do this right the first time.

As stated before, Oracle, MSAccess, and MySQL are not an option.
The actual data source has to be textural based but it will be served within a private infrastructure, not distributed across the internet.

TIA!