Hello Satinder
Looks like your IOS code is working good.. when you do confreg 0x2142 on your router and reset the router, dont you get the initial configuration wizard ? can you send us the exact outputs of the router bootup after you reset the router with 0x2142 ? There are other config register values to put your router on rommon, but none of them ignores the content of NVRAM , as does the 2142 ...
Raj