I've come across an interesting number of people who are confused, uncertain or wrongly taught about how Jesus spent the 36+ hours from 3pm Friday afternoon to dawn on Sunday. Many believe he went to Hell, but this is not Biblical.
The phrase "descended into hell" does not occur in the Bible, but appears in the Apostles' Creed: "...was crucified, dead, and buried, he descended into hell; the third day he rose again from the dead." Even this particular phrase is not found in any early versions of the creed, but only appeared once in AD 390, and even then was intended to mean "descended into the grave". However, come AD 650 it appeared in final form, and spawned a number of explanations since to uphold its literal interpretation. This was not its intention, and is not upheld by Scripture.
One common piece of Scripture used to uphold the argument is from Ephesians 4.8-9 - the Greek text is, however, referring to descending into "the lower regions [which are] the earth". Another, 1 Peter 3.18-20, has been taken to mean that Christ literally visited Hell in his death and preached to the spirits there. The context, as always, is vital, and here it means the work that Christ did through His Spirit in the time of Noah. This also applies in similar vein to 1 Peter 4.6. There are no second chances for people.
And so, when Christ turns to the thief on the cross and says, "Today you will be with me in Paradise"(Luke 23.43), He meant just that. The Sabbath Saturday for Jesus was family time: with His heavenly Father, with his new friend the thief, and with the saints already there too who were true men and women of faith, their salvation secured in Christ's perfect death ("it is finished") and the glorious resurrection to come in just a few hours.