From what I understand (not being a Mac guy), iMovie (already on your system) is very easy. iMovie will do everything you need to put together a recruiting highlight video. If you outgrow iMovie then you purchase Final Cut Pro, which has enough similarity to iMovie to make the learning curve low.
On the PC Side, the two packages that have similar professional (do whatever you want from home to theatrical release) features to Final Cut Pro are Adobe Premier (Mac/PC - I own for PC but do not use) and Vegas (PC - I own and use heavily). Both Adobe and Vegas have "Jr." versions that are essentially stripped down from their bigger brothers. Adobe Premier Elements ($70) and Vegas Movie Studio ($50). Note, there are many other "professional" NLE's (Catalyst, Avid, etc.) that are not relevant ($1,000+).
If you have a mac, start with iMovie (great for beginners) and then move to FCP or Premiere. You can also consider HitFilm (Mac/PC), which is fairly powerful, but not easy if you are a beginner.