Connecting from a BA to JAL flight next week and will have 8 hours from arrival to departure times, giving me approx 3 hours to spend in the city after taking off train/customs times etc.

If I decide to not go into the city (due to flight delay etc) what is T2 like? Is there much to do there during a transit?

Also, will I have to fill out a customs/immigration form for Japan as I am only there in transit?

Regards