renp

A simple WordPress plugin which adds a “scroll to top” button to the bottom corner of the page if the page has been scrolled down. It is compatible with all major browsers and should work with all themes, including 
responsive and high resolution themes.
It is possible to configure the plugin in the admin area for choosing between light or dark colour schemes and size of the button as well.
If your theme doesn’t already contain this feature, you can simply add it by means of this plugin.

Scroll to Top Button

Displays a button in the bottom right corner for smooth scrolling to the top of the page.

arsho

WP-Smooth-Scroll is a plugin that helps users to scroll smoothly to top of the page.
Main features of WP-Smooth-Scroll are:
<ul>
<li>WP-Smooth-Scroll is simple to set up and use.</li>
<li>It has options to select the position of WP-Smooth-Scroll button.</li>
<li>It wont create problem in smaller screen like mobile or tablet.</li>
<li>It is smooth and dynamic.</li>
<li>WP-Smooth-Scroll has an eye catching effect with nice hover effect.</li>
</ul>
Plugin Demo: <a href="http://shovon.info/wp/wp-smooth-scroll" rel="nofollow ugc">Plugin Support</a>

WP-Smooth-Scroll

WP-Smooth-Scroll is a plugin that helps users to scroll smoothly to top of the page.

Scroll to Top Button vs WP-Smooth-Scroll