ubuntu/Kubuntu is great. However, Kubuntu is better as KDE is a bit more comfortable than GNOME(that's my opinion). Mandriva Linux is also very good. It is extremely user friendly. If you want it similar to windows, try out Linspire(formerly Lindows).
If u r a new user to linux. Then Mandriva is the best. You need fairly good linux experience for using ubuntu. Suse is also good but needs some tweaking skills. So start with Mandriva then move to suse if u want more out of Linux.