URL Editing and title editing of my application :(

I run a CodeIgniter application and i want to know what should i do to get the desired result.!

I run a wallpaper website (OFFLINE) on localhost and when i turn off the seo friendly urls,the url is

http://localhost/index.php?/categories/show/1

quite ok!

when i turn on the mod_write setting
the link of category is

http://localhost/Category+Name+1/

an whn i see a specific wallpaper from the category ,url is

http://localhost/Wallpaper_name.html

but i want

http://localhost/category_name/wallpaper_name.html

wat should i do to modify it?
Also i want to edit titles of my pages where should i llook into.?PLEASE SAY

Please HELP DP Members


Here is my HTACCESS FILE FOR URL REWRITING

Options +FollowSymLinks
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond $1 !^(index\.php|install|scripts|fonts|uploads|robots\.txt|sitemap\.xml|favicon\.ico)
RewriteRule ^(.*)$ /index.php?/$1 [L]
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteCond %{REQUEST_FILENAME}.jgz -f
RewriteRule (.*)\.js$ $1\.js.jgz [L] 

Code (markup):

 

You need to edit in PHP Files
Since you're looking through the links provided in php files

 

ya i know that
but since the application wasnt developed by me so i dont know what stands for what

i tried to explore but no success

any one with code igniter experience might help!

 

do it in a controller (maybe index) then dispatch to which appropriate