Famine, Civil war, ethnic violence, massive levels of corruption no funding available for large scale projects
If need be I'll just have the place hit with WMD's, just want the country to be a non factor until 2000, after 2000 India has lost its chance and will be forgotten by history
Well, in OTL India wasn't much of a factor until recently, and look how it surged forward.
To make sure it stays non-important permanently, you have to get rid of it's potential - geography and population. Which amounts to massive genocide not seen in history, because political disunity and intra-subcontinental strife can always end.
That said, interesting. India, while having lots of problems, remained relatively stable, so having bloody internal conflicts there would indeed make it more of a pariah, and famine, corruption and such would follow.
I don't really know, sadly, but perhaps if you would make British more violent, and kill Gandhi and leadership of the Congress instead of imprisoning them... you could have more violent struggle for independence, especially if there is an escalation. And it could develop into internal conflicts all the while removing the powerful advocates of unity (let's put aside it was popular sentiment... perhaps somehow it could change). You still need to maintain some sort of strife after British withdrawal. Maybe British withdraw gradually, effectively relying on collaboration government in later stages, and arming people and using opportunist to keep Indians down? Then for some years India could, perhaps, end in China-like warlordism, and that would stunt it for long time.
That's the best i could come up with. Doesn't sound too good, so perhaps someone else will do better.