What is better in people's opinion? A fluid or fixed forum?
I used to once have a fixed forum which looked fine on the majority of screens that I used, but then I got a widescreen and there was lots of empty space either side. So then I changed to a fluid forum which also looked fine on majority of screens, but then on a widescreen it will stretch all the way across the screen.
If you can't make a responsive layout (that will 'morph' based on the visitors screen width), you should have a fixed layout. I set mine at 980 pixels, which makes the site appear OK from 1024 up (there are not many who use smaller resolutions anymore). The problem with liquid layouts is that, if the visitor has a wide screen (as I do), your content will stretch too much and it will mess up any usability. The lines of text should be short enough to be easily read and a very wide layout will make the lines stretch too much to be comfortable anymore.
Well after trying to look past the GIANT IMAGE BLOCKING THE SITE BECAUSE I'M NOT REGISTERED thing, everything seems stretched.
I don't mind fluid widths, but something like 70% should be used because that seems to work on many screens. Or maybe use a media query to make it so if your screen is wider than 'x' pixels change to fluid width. That would make it responsive.
I prefer fixed width over fluid. I use a 46" and fluid widths just aren't nice to look at when they stretch across the entire screen. Reading forum text should be somewhat like reading on a piece of paper. If the width is too wide, reading can be pretty straining.
Obviously there are ways of making fluid themes have min/max-widths.