Social Security can be saved simply by getting rid of the wage base cap of $106k. If you make the Social Security tax simply flat, rather than the current regressive structure, the program should be fine. I'd be in favor of making it actually progressive so as to add extra solvency, but I doubt that would be necessary. I'd even be willing to look at means testing for Social Security, if the reforms I suggested would be insufficient.
How do we fix Medicare? Well, the health reform law ought to help cut down on health care expenses overall in this country, an it should help keep down Medicare expenses as well. If that doesn't cover all of it (and to be fair, it probably would not), I would suggest cutting the defense budget some more and perhaps creating some new tax brackets for upper income Americans, let's say a 45 percent rate on income over $2,000,000 per year. I wouldn't do means testing for Medicare, mind you, as health care should be a right, not a privilege.
Combine all of that with letting the Bush tax cuts expire for the wealthy, and bringing the tax on investment income back into line with the tax on regular income and the problems should be more or less solved.