Hi,
It was actually how it was in original Virtuemart.
So we decided not to touch it at all, But you can remove this field from there easily. You would need little PHP editings though.
Open this PHP file:
ROOT/templates/<yourjoomlatemplate>/html/com_virtuemart/category/default.php
(default.php, flexv2.php, defaultlist.php etc.. which ever category browse page you are using, make the changes only in that file)
And look for this LINES:
<?php echo $this->searchcustom ?>
<br />
Delete them completely, or change them with these:
<?php // echo $this->searchcustom ?>
then the 1st field, which is "choose product type" field, will be gone.
Cheers.