Bloatware does put you boot and down times a notch. (Im assuming your using Windows XP) Hit Run -> Msconfig -> Startup tab and see anything that you might not want to load at startup and uncheck it. Be careful of what you uncheck cause you might need it. If you want to go further than that, use Run -> Services.msc. A guide can be found here: http://www.blackviper.com/WinXP/service411.htm
Dude, the OP has a system that boots in 20 seconds. He is asking why the PC's MaxPC tests take so long to boot compared to his much older computer. He obviously doesn't need advice on improving his boot times.
To OP, sounds like your rig is going into a sleep state when you hit the power off button instead of fully shutting down. I'd be quite surprised at a system booting in 20 seconds, especially with AVG installed.