We tried that some time ago, and it caused all kinds of problems.
The difficulty with 'discussion' threads is that they rapidly tend to lose focus, and there's always someone who decides to lapse into personal abuse, or some other form of unacceptable content. This forum has succeeded because it concentrates on doing what it's good at - providing help with computing problems. At times we've been criticised for being too strict with our editorial control, but it's precisely that control which has ensured we retain a huge audience of all age groups and both sexes. Anyone can visit here, safe in the knowledge that they won't see bad language, sexual innuendo, or out and out verbal punch-ups.
Whenever one of these discussion threads appears we watch it, and when we think it's wandered off-topic, or is descending into banality we stop it. We'll continue with this policy because we know it works, and because there are a million chat-based forums out there for people who seem to have the time to spend hours talking about nothing in particular.
Spell-checker? I don't think so - you can get a neat little applet that sits in your Internet Explorer tool-bar and spell-checks your text. Called IE Spell it's a free download (although if ever something deserved a donation this does) and you can get it if you