VS 2008 - Freeing Up System Resources

I'm getting a collection of processes, adding them to a ListView, and deleting them from it when needed. All of this is done in a timer. The problem, is that after a while, the app freezes. I think this is because I'm not disposing any variables.

Here's my
VB.NET
Private _processes As New List(Of String)()
Dim killedProcs As New List(Of String)(_processes)
Dim processes As Process() = System.Diagnostics.Process.GetProcesses()
For Each proc As Process In processes
[Code] ....
I tried disposing of my process list, but the IDE wouldn't let me. That's the only thing I thought would need disposing since it is what hold all of the processes.