Does converting my RRSP to a RRIF change how withdrawals are taxed?

Not in the deepest sense - both RRSP and RRIF withdrawals are included in your taxable income when you receive them, so converting doesn't change the fundamental principle that this money gets taxed as ordinary income eventually. What does change is the mechanics around how and when that happens.

An RRSP gives you discretion: you decide if and when to withdraw, and there's no requirement to take anything out in a given year. A RRIF, by contrast, comes with a mandatory annual minimum withdrawal that you must take and report as income every year, whether you need the money or not. Withholding tax is also calculated differently in the two situations - a discretionary RRSP withdrawal generally has withholding tax applied based on the amount withdrawn, while a RRIF's mandatory minimum withdrawal and any amount withdrawn above that minimum can be treated differently for withholding purposes. This distinction between the tax treatment of the income itself, which stays the same, and the mechanics of withdrawal and withholding, which change meaningfully, is a common point of confusion, and understanding it helps you plan your actual cash flow and tax withholding more accurately once you convert.