Step 1. Observe your desktop. There you will find 2 flashing computers on your taskbar. (in the notification area - Bottom Right )
Now Right Click the two Flashing Computers (LAN of ur ISP), and select the option "Open Network Connections"
Step 2:- After completing Step 1, you will have a window on your desktop, showing 2 LANs, one is your ISPs, and other one is your Hamachi's LAN.
On that same window, above on the Status bar , (See in the Fig.), there will be an option "Advanced". Click on "Advanced" and then click on "Advanced Settings".
Step 3:- Another Small window will pop-up as you Click on "Advanced Settings".Here you would be able to see a List of LAN networks on your Left. In this Image, Hamachi LAN is on the second position. You have to bring Hamachi Netwotk on the first position, on top of the Network List.
This Step Would Be possible by the use of the "Scroll" given on the Right Side on the Same pop-up window.
After bringing hamachi on top of the list, select "OK" given in the pop-up. Thats it, You're done.