How to force "https://" to all pages and resolve mixed content issue?

Mine is 2.0.3.1 and my website is LinensnCurtains.com and my store is in subfolder /shop

Issue 1:
Mine is ssl secured site but its home page does not show https... rather showing "not secure" site. checkout page is secured.
I already change both config.php files with https in place of http in all urls there in HTTP and HTTPS section.
I did not understand what changes are required in .htaccess for forced https on all pages. My https file is

RewriteEngine On
RewriteBase /shop/
RewriteRule ^sitemap.xml$ index.php?route=feed/google_sitemap [L]
RewriteRule ^googlebase.xml$ index.php?route=feed/google_base [L]
RewriteRule ^download/(.*) /index.php?route=error/not_found [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !.*\.(ico|gif|jpg|jpeg|png|js|css)
RewriteRule ^([^?]*) index.php?_route_=$1 [L,QSA]

Please suggest what changes are required here to force https on all pages a i feel people seeing "not secure" website on home page will force them to leave website without buying.

Issue 2:
When i checked my site with WhyNoPadLock.com, it gives following mixed content error.

Form Failure
A form with the action of "http://www.linensncurtains.com/shop/ind ... y/currency" exists in the source code of the tested page.
This form needs to be updated to use "https://www.linensncurtains.com/shop/in ... y/currency" or another secure URL for your padlock to return.

How to resolve this?

Please help me suggesting what changes are needed for both of my site.

Thanks and Regards
Pooja

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