If you're on a budget I'd recommend Sony Vegas Movie Studio or Adobe Premiere Elements (Vegas is probably the better option and is usually cheaper - you can also buy Sony Sound Forge Audio Studio for audio editing if you require that).
Unfortunately there no good free video editing solutions, but since you can get Vegas Movie Studio for around £40 and Premiere Elements for around £60, they are usually your best options and miles better than any free solution. You can usually get Vegas Movie Studio bundled with Sound Forge Audio Studio if you pay a bit more, and you can buy Premiere Elements with Photoshop Elements too which is good for video and photo editing on a budget.
If you can afford to spend more I'd get a Creative Cloud subscription and go with Adobe Premiere Pro and Adobe Audition which should cover you for video and audio editing. If you want to render effects then you can also get Adobe After Effects on that subscription too which integrates really well with Premiere Pro. Worth it!
I used Vegas Movie Studio for years before I started learning how to use Premiere Pro CS5.5 and then I moved from CS5.5 to CC 2014, and now CC 2015.