I have a pretty large site with vbulletin forum. I need a stable OS. What do you guys recommend. I was recommend to install Opensuse ...any suggestion on os for me ?
I use suse since 1998 now since 2006 on my root server again opensuse zero problems however I also use suse also offline since 1998 whatever you chose I always recommend to use the same dist as you have offline to assure you have a testing environment and plenty of practice when needed my host - hetzner.de - offers opensuse LAMP images preconfigured easy to install in the NEWEST versions may be your host also has something fully supported for you
We host for big vBulletin forums with 500+ members at any time on CentOS boxes without trouble. CentOS is built from RHE. I dont have any experience with SuSE or Gentoo though.