Should I buy a new laptop?

I'm going to online school next year so I will need a computer. My laptop is 2 years old, and to replace everything that needs fixed it will be about $200. The new laptop I would buy is $500. Theres nothing "majorly" wrong with my laptop, other than the touch pad is broken, and the battery is shot. I used to have limewire and frostwire on my computer, so i'm a little afraid my laptop has a virus. Should I replace my laptop?