Martyn Williams is omitted after winning his 99th cap while leading Wales to a 28-13 win over Argentina on Saturday.
Prop Gethin Jenkins goes despite not having played since January due to toe and calf problems.
Likewise Stephen Jones is included having not appeared in Wales' August warm-ups against England and the Pumas.
Wales coach Warren Gatland admits taking loose-head prop Jenkins to a tournament in which they face South Africa, Samoa, Fiji and Namibia is a risk.
Jenkins underwent toe surgery in January and did not figure in any of Wales' August games because of a calf problem.
"He could potentially be fit for us for the first game against South Africa," said Gatland.
"We're looking perhaps at the game against Samoa, bringing him in and hoping he's going to be alright for that.
"He is an important, quality player - we're taking a little bit of a risk on Gethin, but we know how good he is."
There is also no place for controversial scrum-half omission Dwayne Peel, of Sale.
Hooker Richard Hibbard also misses out after suffering an ankle injury in Wales' win over Argentina.
Cardiff Blues openside Warburton is Wales' youngest World Cup captain.
His chance to do so comes after hooker Matthew Rees was ruled out with a neck problem.
Warburton's arrival at Test level signalled the beginning of the end of veteran fellow Blue Martyn Williams' Test career and he leads Wales into the tournament having led his country only three times.
Williams' only chance of winning a 100th cap would come if Wales need injury cover during the tournament.
Gatland said: "If we had gone 17-13 [forward-backs] on the split we would have taken two sevens.
"We think we've got not a bad seven who's leading the side at the moment.
"We think he's world class and I think Martyn's well aware of that."
Gatland acknowledges having only one openside specialist at his disposal is also something of a risk, but said: "We feel Dan Lydiate can cover there if there was an injury during a match.#
"And if Sam gets a serious injury then we are going to have to look at a replacement."
Scarlets fly-half Jones pulled out ahead of Wales' 23-19 defeat by England on 6 August at Twickenham with a calf injury.Gatland explains Cup choices
He also withdrew from Wales' bench ahead of the win over the Pumas, but goes to a fourth World Cup.
Lee Byrne is the only specialist full-back in the squad that includes once-capped scrum-half Lloyd Williams, the son of former Wales and British and Irish Lion Brynmor.
Lloyd Williams came off the bench against the Pumas having played in the Barbarians' win over Wales in June.
Wales were unable to consider injury victims Morgan Stoddart and Gavin Henson for the tournament.
Preliminary tournament squad members Scott Andrews, Jonathan Thomas, Justin Tipuric, Josh Turnbull and Gareth Delve also also failed to make Gatland's party.
WALES 2011 RUGBY WORLD CUP SQUAD
Forwards: Gethin Jenkins (Blues), Lloyd Burns (Dragons), Huw Bennett, Ryan Bevington, Adam Jones, Paul James (Ospreys), Ken Owens (Scarlets), Craig Mitchell (Exeter), Bradley Davies, Sam Warburton (Blues, capt), Luke Charteris, Danny Lydiate, Toby Faletau (Dragons), Ryan Jones, Alun Wyn Jones (Ospreys), Andy Powell (Sale Sharks).
Backs: Michael Phillips (Bayonne), Lloyd Williams (Blues), Tavis Knoyle (Scarlets), Jamie Roberts (Blues), James Hook (Perpignan), Jonathan Davies, Stephen Jones, Rhys Priestland, Scott Williams (Scarlets), Leigh Halfpenny (Blues), Lee Byrne (Clermont Auvergne), Aled Brew (Dragons), Shane Williams (Ospreys), George North (Scarlets).