repartition of server

The admin before me set up the server terribly. There is only 800MB free for the system (C:) drive. The D: drive has 2GB. There are two other drives that have 10GB and are being used for general file storage. I want to reconfigure but my boss doesn’t want to buy ServerMajic, which I know would be the easiest. Is it risky to back up data, delete partitions and then recover everything? I am scared about doing that. I need the disk space though for the system drive! I can’t even upgrade the service pack or anything!