Since you are already getting the value for the drop down, your question is how to get the text (display) for it.
Here's a way to do it.
In the declaration for the button that submits your form on page 1 include an onClick handler:
<button onClick='prepSubmit()'>Go To Page 2</button>
The form should include a hidden variable:
<input type=hidden name=ddText>
Now include some javascript code:
<script>
prepSubmit() {
var frm=document.forms.formNameGoesHere
var dd=frm.elements.ddIdGoesHere
frm.elements.ddText.value = dd.options[dd.SelectedIndex].text
frm.submit()
}
</script>
Csaba