Plans with JR East Pass

I'll be going to Tokyo in May on a package with 7 nights accommodation in Shinjuku. I am thinking of buying a 5-day JR East pass as I am hoping to go on day trips out of Tokyo. Naturally I hope to make full use of this pass and maybe with the last day ride to Narita airport? Would these places I choose to go covered by the JR East Pass?
Yokohama and Kamakura - 1 day
Tateyama Kurobe Alpine Route - 1 day trip, plan to walk the snow corridor only, so might go from Ogizawa to Murodo and return, is this too rush?
Kawagoe - 1 day
I want to try the shinkansen to another town where I can stay overnight in (not too expensive though) and eat wonderful fresh seafood as well, any suggestion? Can I do Hachinohe in 1 day? Any suggestion/advise are very much appreciated. Thank you.

Yokohama and Kamakura

The JR train trip from Tokyo to Yokohama and Kamakura is covered, but much cheaper by regular tickets than by JR East Pass.

Tateyama Kurobe Alpine Route

JR transportation to Shinano-Omachi Station is covered, but transportation along the route is not covered. On the other side of the route, the JR train trip between Toyama and Naoetsu is not covered by the JR East Pass, either.

A round trip Tokyo - Shinano-Omachi via Matsumoto costs about 15,000 yen, therefore, the JR East Pass could be an attractive option.

plan to walk the snow corridor only, so might go from Ogizawa to Murodo and return, is this too rush?

If you leave early in the morning and it is not a too crowded day, it should be possible without a feeling of being too rushed. But there will be lots of train riding involved.

Kawagoe - 1 day

Access by JR is covered, but considerably cheaper by regular tickets than the JR East Pass.

Can I do Hachinohe in 1 day?

Yes! It takes "only" three hours one way to get there from Tokyo.

Thks, Uji for ur valuable info, another question, If i take the shinkansen to Takasaki for Kusatsu onsen, which limited express can I transfer to go to Naganohara Kusatsu-guchi Station? i read of the Kusatsu Ltd express (which is under JR East as well?) but can't find the timetable for it, is it still running? appreciate

Access to Kusatsu is explained on the following page:
http://www.japan-guide.com/e/e7403.html

i read of the Kusatsu Ltd express (which is under JR East as well?) but can't find the timetable for it, is it still running?

It is still running and fully covered by the Japan Rail Pass. The timetable is here:
http://www.japanrail.com/pdf/timetable_fare/timetable_f...