if it is the utter **** called trend micro they give us from school, get rid of that NOW.
For the record, I like Trend Micro - I'm not sure what version your school gives you, however.
Furthermore, there's no perfect antivirus, and various programs are more adept at stopping different threats. However, I would never direct anyone to McAffee or Norton, which from all accounts I've heard are bloated programs in the extreme with marginal effectiveness. I used to have two different programs simultaneously running on my machine, Trend Micro and SpySweeper. I no longer have SpySweeper installed, but it is a nice program, and I would advocate it along with Trend Micro.