ASP.Net Revisions for Web Forum

We have a web forum and need to make some revisions. Here's a run down of what we need one: 1) there are a lot of spammy comments left my people that we'd like erased. The forum is written in ASP.Net and we've created a list of 500 or so users who were spamming the site, and we'd like all of their posts erased off the site. 2) On top of this, we also have some advertisements on the right column and the bottom of the site that we would like taken off every page. Sitewide changes are pretty easy to make on this site by all accounts. 3) We'd like to replace the advertisements with a web form to collect people's information who are interested in our service. 4) There are also some sections of the web forum that we would like eliminated altogether.