Here are some instructions on how to write a basic System DSN to a sql server database. http://www.faqts.com/knowledge_base/view.phtml/aid/33020. The process is the same for most database types that use ODBC. Your DBA will be able to help you.
Once this is done, you need to reselect the DSN your Crystal report is looking ofr from within Crystal Reports. The CR knowledgebase has some articles that will help.
Now you have a report which point to a system DSN, write a new schedule in CRD as normal.