Virgin Import of 4.0 or 4.1 DB Schema Yields Problems with 3 Tables and Their Keys

When I import either the 4.0 or 4.1 .mysql schema and "check table" right after import (having never even logged in) with phpMyAdmin it tells me there are some errors:

Problems with indexes of table `node`
 PRIMARY and INDEX keys should not both be set for column `nid`
 More than one INDEX key was created for column `status`
Problems with indexes of table `term_hierarchy`
 PRIMARY and INDEX keys should not both be set for column `tid`
Problems with indexes of table `term_node`
 PRIMARY and INDEX keys should not both be set for column `tid

This is when bringing the schema in to the latest MAMP or the older versions my host is using: MySQL 4.0.24, phpMyAdmin 2.7.0-pl2

Having made relational dbs in FileMaker Pro I understand that the primary key is *the* reference to use when looking for a specific row, and that indexing makes finding it faster, but am not knowledgeable about mySQL...but like the text output that can be studied.

I searched Drupal.org a number of times and found a few things that seem to be the same or similar, but I can't find any EXPLANATION off why or what to do.

This node http://drupal.org/node/63571 indicates he has the exact same problem/error message as me, but he indicates 1) it's normal 2) he fixed it. But I don't know the answers to either of those...

I have since learned that the errors in question are not always necessarily errors, per the designers of phpMyAdmin, and have since managed to produce a working installation (reproducible!) that does not have this same problem.

This post http://drupal.org/node/58942 seems to indicate, again, the exact same problem, but points out the problem in the .mysql file... This post is marked a bug and not closed (unlike the former one that is closed.)

Finally this post http://drupal.org/node/21876 seems to be the same problem I have. Someone points out the MySQL docs for what keys and indexes are, and goes one to write:

don't think this will interfere with regular operation; however, if it does, just delete the duplicate indexes (under "table structure" in phpmyadmin).

My thoughts are:
1. I don't really feel comfortable changing the base structure of the db as it shipped
2. Why is this problem happening with a virgin install?
3. What can or should I do? I have no interest in adding more content if my db is corrupt or is on its way there.

I have already done much work on my site and would have posted this someplace else, but the more I backtracked...I found myself finding the problem right where I started...in the virgin DB schema (or so it seems).

Many TIA.