Windows 2008 Server / IIS7- experiencing a few odd issues.

Background information: - We are a University in New Jersey, in Jersey City (NJCU), in IT Department. - We host our own servers on site. - The server that is experiencing some issues is an Windows 2008 Server running IIS7. - It only started displaying the issues a few months ago. Prior to that it was fine. - I don't believe we installed anything since that time that should have caused the issues, but am not fully sure. It is possible. Issues we are experiencing: There are two primary issues that we are experiencing. 1. I have noticed in two different (completely separate) web applications that use an HTML editor (to edit webpages, etc.), that upon my logging into the web application (or any user on our campus as well as from off campus) some of the icons in the HTML editor (for things like copy, paste, link, font name, image, alignment, etc.) don't show up and appear with a red x instead. When we hit refresh, very often the icons that show vs the ones that don't show will change. So, it's not specific icons that don't show all the time. It seems to change when we refresh the page. But when using Internet Explorer, with the option of "Show picture" .. I can one by one tell the browser to show the picture. So also .. the issue isn't that the images are no longer on the server. They are .. but the images just don't seem to show up (all the time) as they did previously. Something appears to be blocking them from showing, randomly and sporadically. We need to find out what is causing this issue and have it fixed. Again, this is happening in two different web applications (that are installed on the same server). One works with a simply .mdb database file and the other connects to a MSSQL database. One application is written in ASP and the other is written in ASP.NET. 2. The other issue is that we have been noticing, over the past few months (which wasn't happening previously) .. and seems to have started at and around maybe the same time as the first issue, where one of our application pools (in IIS7). This is the default application pool. It seems to be stopping quite often throughout the day, almost every single day from what I see, and then often will restart. But sometimes it doesn't restart and brings down the applications that are using this application pool. It is very odd and we need to find out what is causing this and get this corrected so the application pool (or what ever is shutting down or causing various applications on the server to shut down) will not keep giving us trouble. We have various applications on the server that run, such as a Help Desk system (.php), Website CMS (.asp), Survey/Form System (asp.net), etc. And when the application pool shuts down, it causing some or all of these applications to stop working. It will then often display a 503 error message. Sometimes I can restart IIS or the application pool to fix the issue, but sometimes it requires me to restart the entire server. We need someone who has experience with Windows 2008 Server, IIS7, PHP, ASP, ASP.NET to help debug and fix these issues. Please let us know if you can help. Sincerely, Gary