This is a very good route, I am glad you picked this one for ur parents. it's just flying out of windy city is a hassel once they are in plane and especially when they land in delhi they feel homely, no doubt about it. I have travelled this route earlier and no problem at all. GoodLuck, just as much as we want to bring our parents out to US, it's even getting harder these days to find travel partner with so many options wide open.