Golden Week bad idea?

Is it a bad idea to visit Japan during the Golden Week?

I'm thinking of going to jp just a few days before GW starts and leave a few days after GW ends.

Are most shops & restaurants closed?

I've been to jp many times. I haven't visited jp on the month of April & May.

Things are incredibly busy for golden week, and often hotels are booked long in advance. I would try going after golden week when things calm down, but hey if you can get a hotel then go for it!

"Are most shops & restaurants closed?"

It is exactly the opposite.... many shops & restaurants will be full, tourist areas will be crowded and the whole time will be very busy!!!

Best to leave it until after golden Week.

Through no choice of timing I did Golden Week a couple of years ago. I had no trouble pre booking my business hotels ( TOYOKO ) and only the slightest difficulty with seat reservations on shinkansen trips. I resorted to non reserved and always got a seat. It was incredibly busy and that lent to the experience. There were enough people travelling to cause train delays on shinkansen and other services.It's not for the faint hearted but I managed and I was then in my late 50's

All shops and restaurants are open during GW.
But it will be full by tourists. Hotel set special price for GW, so it will be expensive during GW. Reservation of sheets for shinkansen will be difficult. At some major visiting site, you have to be on line for several hours. Of course, there are many special event, like traditional festivals although it will be very crowded.