Geeklog

I'm trying to find out how to do a couple things before I tinker too much with the files on my site.

I use the same skin as this site, but I want to expand the entire table of the page to cover about 95% of the page. (So you see less dark grey, and there's more room for content)

Then I want to increase my forum avatar size to a maximum of 160x320 pixels.... The increased width of the page should make it look quite nice

Anyone out there know which files I need to change? Your help is greatly appreciated.