Difference between inbreeding and interbreeding
You are basically correct. Most common usage in my experience:

Inbreeding refers to sexual reproduction between genetically closely related individuals, within a species. Inbreeding will increase the relatedness between individuals in a population.

Interbreeding refers to reproduction with another species (or race), and is often used as a synonym to crossbreeding or hybridization (when referring to hybrid offspring from two different species/races/breeds, not DNA hybridization). This is also how 'Interbreeding' is defined in the Oxford English Dictionary. However, 'Interbreeding' is sometimes used just to signify that two individuals can breed and have viable offspring ("...these two individuals can interbreed..."), and under this usage this can also include/overlap with inbreeding.

The latter usage can be seen in the Species article in Encyclopædia Britannica, online:


  Species, in biology, classification comprising related organisms that share common characteristics and are capable of interbreeding.
  ...
  Interbreeding only within the species is of great importance for evolution in that individuals of one species share a common gene pool that members of other species do not.