I want to make my site more user friendly and so I would like to replace select list with an image list. Is it possible to display ordinary select list as an image list? Is there a module that would allow me to do so or do I need a custom code for this fetaure?
There is in fact a module that can do this. It's the Select with style module.
You'll have to use some jQuery help for displaying images as options in a select form element. Check out this collection of plugins.
You may also have to implement your own Form API element type using
hook_element_info() to output the markup that your chosen jQuery plugin needs.
Lastly, you haven't said which select list you would like to change, but if it's an existing form, you might end up implementing