Finally I got fed up with my slow laptop and since the memory thing did not work out, I was feeling desperate. So I decided to byte the bullet and spend couple of thousand more rupees and ordered a hard-disk and a mouse from Amazon.
In couple of days got them too. I was going to be out of town for weekend, so I quickly put it all together and then put Ubuntu Mate 17.10 on it.
Then watched couple of episodes of a tv show and did bit of web browsing. And I can say it all has been working great. The new hard disk is plenty fast. The Logitech mouse is serviceable. The pointer a bit once in a while but otherwise it's fine.
This has greatly improved the usability of my age old laptop.