I've found this to be easy for all involved:
- Create a webservice method such as DoSuchAndSuchProcess
- Create a console app that calls this webmethod.
- Schedule the console app in the task scheduler.
Using this methodology all of the business logic is contained in your web app, but you have the reliability of the windows task manager, or any other commercial task manager to kick it off and record any return information such as an execution report. Using a web service instead of posting to a page has a bit of an advantage because it's easier to get return data from a webservice.