Depreciation question...

First off, thank god for you guys. We all appreciate you lending your experience to these forums to help us avoid costly mistakes.

Currently I’m in the paralysis of analysis phase of my investing career, as I accumulate enough cash for a DP on a house. My question is in regards to depreciation. I plan on acquiring a 3-4 bedroom house and renting out the rooms to cover my mortgage payments. Is it more advantageous to simply write off the mortgage interest at the end of the year or to actually do accelerated depreciation as a rental property? What resources should I consult that cover this topic more in depth? When I sell this property 3,4, or 5 years down the road, I can use the depreciation of other properties to reduce or eliminate the taxable income from the sale of that first property. Is that correct or am I looking at this backwards??? Thanks so much for your time.