SMS to Text will convert the "text" (which is really text plus xml headers) to actual text that you can paste into any box you can type into.
SMS Backup & Restore will back up the texts, but keep the headers (so they can be restored) so either you have to strip them out manually or the person receiving them has to know how to ignore them. The saved "text" looks something like:
<?xml version='1.0' encoding='UTF-8' standalone='yes' ?>
<!--File Created By SMS Backup & Restore v7.07 on 30/04/2014 16:51:43-->
<?xml-stylesheet type="text/xsl" href="sms.xsl"?>
<smses count="23">
<sms protocol="0" address="1234567890" date="1363367443000" type="1" subject="null" body="
This is the actual text you see in your texting app." toa="null" sc_toa="null" service_center="null" read="1" status="-1" locked="0" date_sent="0" readable_date="Mar 15, 2013 1:10:43 PM" contact_name="(Unknown)" />
<sms protocol="0" address="12345" date="1376457502000" type="1" subject="null" body="
This is the next text that got saved." toa="null" sc_toa="null" service_center="null" read="1" status="-1" locked="0" date_sent="0" readable_date="Aug 14, 2013 1:18:22 AM" contact_name="(Unknown)" />
And so on. The parts I underlined (there's no underlining in the original) are the text you want. It's not difficult to just ignore everything not inside the 'body="xxxxx" part.