Driving to Grinpa

I've booked a package and will be staying in Crowne Plaza Metropolitan Hotel at Ikebukuro, Tokyo. Travelling by public transport with two young children to Grinpa seems long and tedious. Would renting a car and driving there be a better option? Is it easy to drive to Grinpa?

I've never been to Grinpa, but I can say that it's extremely stressful and not worth it to drive in central Tokyo, and for that reason a lot of Tokyo-ers don't even have a driver's licence.

I suppose that if you're used to driving on the left side of the street, you can consider renting a car once you get out of the city. However, depending on the date, the traffic jam to the Gotenba area can be a lot more tedious than public transportation.

Actually, are you sure you want to go all the way to Grinpa? It never occured to me that it was attractive enough to make people travel all the way from another country and through the Metropolitan.