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She need not report the cash, stock, or house on her tax return. However, please remember that the FMV of the house and stock at the date of her Uncle's death is to serve as her basis should she ever decide to sell these.
The money from the retirement plans cannot be rolled over. Here is a piece from the IRS Publication 590. You can read more about this at www.irs.gov
Inherited from someone other than spouse. If you inherit a traditional IRA from anyone other than your deceased spouse, you cannot treat the inherited IRA as your own. This means that you cannot make any contributions to the IRA. It also means you cannot roll over any amounts into or out of the inherited IRA. However, you can make a trustee-to-trustee transfer as long as the IRA into which amounts are being moved is set up and maintained in the name of the deceased IRA owner for the benefit of you as beneficiary.
Like the original owner, you generally will not owe tax on the assets in the IRA until you receive distributions from it. You must begin receiving distributions from the IRA under the rules for distributions that apply to beneficiaries.
Here is a link to Publication 590
As to the reporting on a tax return, lines 15(a) is used to report the gross amount distributed and line 15(b) is used to report the taxable portion of that distribution. As a death benefit there will be no early distribution penalty.The gross distribution and taxable portion may differ due to a number of circumstances and you will need to wait to see the 1099-R at year end. For practical planning purposes you should consider it as all taxable for now. Then you will be taking a safe path.