I have an asp.net 2.0 app written in C# and VS2005. I sometimes have
issues where users leave a page onscreen and then come back to it a
few hours later and try to continue working. Of course, it doesn't
work then. Currently they will encounter some sort of error message
because the session has timed out.

I need to develop a way to handle this!

Some questions:

1) If I want to set my session to timeout at 30 minutes, what should i
set for session timeout both in IIS config and in the web.config file,
for forms authentication.

2) When I am using my online banking website, my webpage automatically
logs me out after a set amount of time. How do I do that with my code?

Thanks in advance for your help!