ISSUE SUMMARY:
How do i set Time Zone to a default value?
What is DST Offset? What is its use?

Login to the site from the Frontend(Please use credentials given in "Misc Information").
Go to "Edit Profile"

Thanks!

Hi Sheetal,

To set default timezone is not possible, because that section is from Joomla system. For further information I suggest you post on Joomla forum.

To understanding DST offset please read this en.wikipedia.org/wiki/UTC_offset :)

thank you!

Thanks for the information.
How do i hide these two fields? I do not want to show these two fields in the the "Registration" and "Edit Profile" page.

to hide it, you need to edit Users->Options->Frontend User Parameters, set to No

thank you!

Setting Users->Options->Frontend User Parameters to No removes Choose language and Time zone.
But it does not remove the DST Offset.

if you wanna to get-rid the DST only, and show the rest user parameters you can use this trick by using css :

.joms-form__group[for="dst-offset"] {
    display: none;
}