It would be about a 30 minute ride on the central line, but
Tayyabs is definitely worth checking out.
No reservations, but the food is incredible. Blows the nearby Brick Lane eateries away by a mile. They're cool about BYO although I think they do Kingfisher beer etc, nominal corkage charge IIRC but the bill has always come as a pleasant surprise for the amount eaten and drunk.
Wingnut - that place in Tooting sounds great, and fairly convenient for us.
Another suggestion that may help the OP more would be to go further west into Southall. I'm afraid I haven't got any personal experience but have heard several recommendations from friends in west London that it's *the* area to go for good Indian food.