Tokyo and Hokkaido in March and April 2015

Would be visiting tokyo & hokkaido in 21 March to 3 April 2015, but have no idea of where to go. Any recommodation?

Suggestions for Tokyo:
http://www.japan-guide.com/e/e2164.html

Suggestions for Hokkaido:
http://www.japan-guide.com/list/e1101.html

I am sorry to say that it is not a very good time of the year to visit Hokkaido. Winter is about to end. And spring has not arrived yet.

How about to visit famous places if you are beginer?
Tokyo area: Asakusa,Ginza,Shibuya
Hokkaido: Sapporo, Otaru
http://www.gotokyo.org/en/index.html
http://japanpockettravelguide.weebly.com/
http://en.visit-hokkaido.jp/

Thanks for the reply!!
As the air ticket is already purchased , we cannot change the location therefore a group of us will be visiting Hokkaido for a short period in 25 March to 28 March. And would like to make full use of it.
Any MUST eat food & must do?

I also will be in Hokkaido from 29March 2015 to 1 April 2015 (3 nights, 4 days), hope to see some snow there. And I know it is not the best time to visit Hokkaido, but I still want to go there. Please give me some suggestion about where should I visit at that time, I intent to go to 1 sky resort, and I will take flight to Sapporo.
Thanks alot

Hokkaido Food:
The amounts of cows means...
European-Styled Japanese Pastry
E.g. Cheesecakes, tarts, rolls...
Japanese Chocolate
E.g. Royce, Rottakei
Milk
Wagyu Beef

Being an island means...
Seafood
E.g.
Sashimi
Sushi
Grilled fish with lemon

Having ports means...
Western influence
E.g. Curry Rice

Chinese Influence
E.g. Shio Ramen origniates from Hokkaido

Not being summmer thus no agriculture plant produce

It is winter
Please head to an onsen to warm up
The most famous being Noboribetsu
However, there are many... MANY other options available. Take your pick

There is snow... View even more of this white fluffy goodness by going towards mountains
E.g. Daisetsuzan

Possible plan
1 day Otaru
1 day + 2 night Daisetsuzan or Sounkyo for Ski/Build snowman/Onsen

OR
1 day and night Otaru and Sapporo
1 day Hakodate
1 night Noboribetsu

Thank Joshua alot!