Having dual-booted various flavors of Windows and Linux for years now, allow me to pass along some advice...
If you haven't already, download and burn a Kubuntu LiveCD -- and boot from that before you try an installation. Anything that does not work well (e.g., sound, video, networking, wireless) is going to range from trivial to impossible to fix after you install.
First, BEFORE you do anything to change your machine, use the Backup function in Windows 7 to create and burn a Windows 7 Repair CD. If you corrupt your Windows 7 boot (happens when folks make mistakes in dual-boot setups), you will need this to get Windows 7 boot back.
Second, use the Windows 7 Disk Management utility to shrink your Windows 7 OS partition to make room for Linux. Using the GParted Linux utility runs the risk of corrupting the Windows 7 OS partition, rendering it unbootable. Don't allow the Kubuntu installer to shrink your Windows 7 OS partition, either.
Third, go to the Ubuntu Forums, Installations and Setup subforum with any questions you have. Kubuntu is basically Ubuntu with the KDE desktop and libraries installed.