I wanted to know which Forum Software like PHPbb/SMC etc. is most reliable and why would you suggest it?? Please help as i want to start a new forum for my site
Parag, That depends on your needs. Both phpBB and SMF are tried and tested forum apps, having great communities, vast number of mods, themes, etc. I would say - go through the default features of either of these and decide on a theme you want to use. Which ever fulfills your needs, go for it. If you are willing to shed some money, vBulletin is an excellent commercial product. And btw, myBB is a very good "light-weight" free forum app.
You should install all the free ones or get to a test site to see how they perform. I have worked with most of them and decided MyBB is the best so far. Still, some love phpBB and SMF, though they are not my choice anymore. I wouldn't pay for VB or IPB though. Have done this in the past and now I regret my decision.