I've read only good comments about MSE myself. Who is your Internet Service Provider (ISP) ? Many ISPs provide one of the better commercial ones (e.g. Norton, vastly improved from just a couple years ago, when it was an atrocious resource hog). I've also used AVG.
I would also recommend Firefox with the Adblock+ and NoScript add-ins. Not letting malicious scripts run also prevents poohware from getting on your system.
Like Arson94 points out though, staying safe is as much about your habits as about whatever protection you get.