Repairs: Contact Landlord or Do It Yourself?
Keep in mind, if the needed repair is a result of "normal wear and tear" your landlord is responsible to pay for the repair. Examples of normal wear and tear are things like the door knob becoming loose, the window not opening correctly, or the heat not turning on. These are things that sometimes breakdown over time and not caused by damage or negligence on the part of the tenant.
If the needed repair was caused by damage or negligence on the behalf of the tenant, then the tenant is responsible for paying the repair costs. Examples of negligence or damage include pipes bursting in the winter because you left for an extended period of time with the heat turned off (negligence), putting a large hole in the wall, or throwing an object and breaking the window.
If the broken things belongs to you, then you don't need to bother your landlord about the repairs as they are not responsible for your personal property. Finally, remember that just because you are handling the repairs yourself doesn't mean you should do them yourself. Always make sure that repairs are completed by a qualified and if applicable licensed professional.