Just think it out logically, if $main not equal "catalog" or $main not equal "help". That statement will evaluate to true if main doesn't equal help or catalog. If it equals catalog then it doesn't equal help so it is true.
{if $main neq "help"}
{if $main neq "catalog" or $current_category.category neq ""}
{include file="customer/bread_crumbs.tpl"}
{/if}
{/if} should do the trick. (I think)
About changing the submit button title, use webmaster mode to determine the template that the button is being called in. With the default skin the file is: /common_files/customer/help/contactus.tpl
Around line #259 find:
{include file="customer/buttons/submit.tpl" type="input" additional_button_class="main-button" assign="submit_button"}
Change to:
{include file="customer/buttons/submit.tpl" type="input" additional_button_class="main-button" assign="submit_button" button_title="Send Email"}
The key piece is the button_title="Send Email" and you could also use button_title=$lng.lbl_button_send_email which would actually be more correct, but you would need to create that language variable. Just go to the admin Content > Languages and select the English language. Then add a new variable "lbl_button_send_email" and value "Send Email".
Luke, at this rate you'll be an X-cart master in no time! Good luck.