A little Update.....
After putting in extensive research online, followed by some shopping, both online as well as offline, I finally upgraded my whole system except the Processor, the HDD's, the ODD and the cabinet.
What I got for it were:
1. The much needed motherboard - MSI G41M-P26 for Rs. 2518 from Flipkart
2. Since the motherboard supported DDR3 RAM, I had to change it too. Got a Kingston Value RAM 4GB (1333 Mhz) for Rs. 1300
3. The cause of all this - the PSU had also to be changed. So I got a Corsair VS 450 for Rs. 2300.
4. Got a Cooler Master CPU cooler from Flipkart for 281 alongwith the motherboard. But, its cooling was not so good, and moreover, it had just a 3 pin connector as against the 4 pin connector on my stock cooler, which helped in adjusting the Cooler Fan RPM when the CPU temperature rose above a limit (60 degrees in my case). One fine sunday, thought to swap the internal coil and circuitry of my older CPU cooler (whose one of the fan blades broke and was fixed by me using feviquick) with the one in the new one. In this process, I just got both the CPU coolers non functional. Though, I was somewhat successful in getting it done, but, then the resulting cooler didn't rotate when my cabinet stood upright. So, finally thought of changing the CPU cooler again. This time, I again searched online and offline, and finally ordered Cooler Master TX3 EVO from Flipkart for Rs. 1411.
5. My CRT monitor has also aged and had become a hub of problems. SO, I changed it too with an AOC 2243Fw2k LED backlit LCD monitor for Rs. 8610 from Cost to Cost, Nehru Place.
Long story short... So, in the last 1-1.5 months, I've spent around 16.5K to revive my 7 year old Pentium 4 machine, that too with most of the components, future proof, which can be used again when I'll be upgrading in a year or so.