HP's are so loaded with bloatware that many tech enthusiasts find a clean copy Windows 7 DVD to clean reinstall without the factory bloatware. Until then, they turn off all the useless utilities in msconfig>Startup including the HP Wireless Manager which adds 30 seconds to bootup and drags on the CPU - config Windows 7 superior wireless connection in System tray.
If you find you don't need or want those useless utilties as well as other programs, you can uninstall them using Revo uninstaller in Advanced mode: it will run Windows uninstaller, but when prompted to restart, click Next instead to delete all the leftover registry keys and files Revo cues up
in bold.
As suggested, if you browse that HP utilities partition with folders unhidden in Control Panel>Folders options>View you can decide whether you want to keep any of those utilities. If not go ahead and delete it to create your fourth Primary partition. You may need to use free Partition Wizard to do so:
Partition Wizard : Use the Bootable CD