My assumption is that you have a Microsoft windows operating system, because a dell laptop would normally have a windows operating system preloaded. You need to be aware of the fact that partitioning your dell laptop will mean that you lose all the data stored on the hard disk. One needs more information about your laptop to provide a meaningful answer. The operating system as well as its current state.
No partitioning software will cause data loss. PartitionMagic and Built-in Partitioner in Vista and 7 all work fine. If you're using XP, you need PQMagic. For Vista and 7, the built-in is ok but can't move data around so it works best after a clean install or with a good defragger like PerfectDisk that can move everything around including pagefiles and system restore images.