How I configure my .htaccess to optimal results??

I hace a question:

The .htaccess file is the following:

# Comment the following line (add '#' at the beginning)
# to disable mod_rewrite functions.
# Please note: you still need to disable the hack in
# the vBSEO control panel to stop url rewrites.
RewriteEngine On

# Some servers require the Rewritebase directive to be
# enabled (remove '#' at the beginning to activate)
# Please note: when enabled, you must include the path
# to your root vB folder (i.e. RewriteBase /forums/)
#RewriteBase /

#RewriteCond %{HTTP_HOST} !^www\.yourdomain\.com
#RewriteRule (.*) http://www.yourdomain.com/forums/$1 [L,R=301]

RewriteRule ^((urllist|sitemap_).*\.(xml|txt)(\.gz)?)$ vbseo_sitemap/vbseo_getsitemap.php?sitemap=$1 [L]

RewriteCond %{REQUEST_URI} !(admincp/|modcp/|cron)
RewriteRule ^((archive/)?(.*\.php(/.*)?)?)$ vbseo.php [L,QSA]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !^(admincp|modcp|clientscript|cpstyles|images)/
RewriteRule ^(.+)$ vbseo.php [L,QSA]

If my forum domain is www.foroexample.com and http://foroexample.com (I can enter from anyone, with or without www)...

How must I change the .htaccess file??

What should I modify?? Do I have to let the #??

Please!! I don't understand anything!!

I configure the .htaccess file like this: (my site is buforo.com with and without www)

<IfModule mod_security.c>
SecFilterEngine Off
SecFilterScanPOST Off
</IfModule>

RewriteEngine On
RewriteRule ^((urllist|sitemap).*\.(xml|txt)(\.gz)?)$ vbseo_sitemap/vbseo_getsitemap.php?sitemap=$1 [L]

# Comment the following line (add '#' at the beginning)
# to disable mod_rewrite functions.
# Please note: you still need to disable the hack in
# the vBSEO control panel to stop url rewrites.
RewriteEngine On

# Some servers require the Rewritebase directive to be
# enabled (remove '#' at the beginning to activate)
# Please note: when enabled, you must include the path
# to your root vB folder (i.e. RewriteBase /forums/)
#RewriteBase /

RewriteCond %{HTTP_HOST} !^www\.buforo\.com
RewriteRule (.*) http://www.buforo.com/$1 [L,R=301]

RewriteRule ^((urllist|sitemap_).*\.(xml|txt)(\.gz)?)$ vbseo_sitemap/vbseo_getsitemap.php?sitemap=$1 [L]

RewriteCond %{REQUEST_URI} !(admincp/|modcp/|cron)
RewriteRule ^((archive/)?(.*\.php(/.*)?)?)$ vbseo.php [L,QSA]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !^(admincp|modcp|clientscript|cpstyles|images)/
RewriteRule ^(.+)$ vbseo.php [L,QSA]

Is it OK??

Yes, that is ok.
More details here: [How to] Setup www.yourdomain.com or yourdomain.com (www vs. non-www) - With .htaccess 301 redirects

Thanks a Lot.