Having not played any form of cricket since a Twenty20 victory against India in early September, England's weary team are rested after a testing year on and off the field.
Between now and the World Cup, in Australia and New Zealand starting in February, England's schedule is made up entirely of limited overs cricket and Cook believes that provides them with the perfect platform for success.
"Without a doubt, this is our best chance," Cook told a press conference ahead of their seven-game ODI tour in Sri Lanka.
"This goes back a few years in planning and asking why our World Cups have not gone as well as they should have.
"Since 1992, we have not done ourselves justice in any World Cup. The ECB have planned to make sure we have the guys fresh and ready to go for the World Cup.
"We have a great opportunity and I, for one, am excited about playing one-day cricket without having Tests in the forefront."
England have lost five of their last six one-day series but the 29-year-old pointed to the absence of key personnel on those occasions.
"We haven't had our full-strength side since the Champions Trophy (in June 2013). Priorities change. We obviously had back-to-back Ashes series so a lot of the guys were rested from one-day cricket. That is not the case now.
"We have a full-strength side, we have guys who are desperate to get a World Cup spot and we have time to really focus on us as an England one-day side.
"The last time we were able to do that we were very dangerous. A lot of one-day cricket is played on the back of Test series when guys are tired and you can't do as much work on your skills.
"We have this five-week tour ahead of us now and we can't use that excuse now."
England face Sri Lanka in the first ODI on Nov. 26.
(Reporting By Tom Hayward; Editing by Ian Chadband)
