Ranking Question / Possible?

[JakeS]

Hi there,

I work for a municipal Government in Canada and we are having great
difficulty getting a high quality web search implmented on our 8,000 page web
site. We are trying to refine our Index Server search engine but some
developers are telling us certain things aren't possible or too complicated.
I was hoping an expert here could help me determine if we can proceed with an
idea we've developed.

Basically we would like to use a query that ranks as follows (eg. quick
brown fox) :

If a user enters phrase with no quotes:

- search for each word in the index's documents
- if 3 words are found 1 time each in a 1 document and twice each in
another, rank those two pages pased on there being 3 words found and hits for
each word
- rank the page with several hits of the same 3 words above pages with
only one hit of each word
- rank pages where 2 words may have been found 1000 times on one page
lower then any pages with each word found at least once.
- rank pages where 1 word may have been found 1,000,000 times on one
page, lower then any pages where 3 or 2 words were found at least one time

If user enters phrase with quotes (e.g. "Quick Brown Fox") :
- search for the phrase and return no results if phrase not found (no
partial phrase search done at all)

It would seem to me that this is the most logical way to rank search engine
hits. Could anyone tell me how to get this rolling or if its even possible?
Is there something I have missed in my description? Would you rank search
results differently?

Thank very much for any help anyone can give in this matter.

- JakeS