This account describes 90% of the PowerPoint presentations I've witnessed, and I've seen thousands.
If you don't want to be that guy, I think I can help.
A great presentation requires ideas and techniques that have nothing to do with technology -- and they're well known. Go to Garr Reynolds, Presentation Zen and Seth Godin for everything you need to know about how to deliver a great presentation.
In addition to all that, here are three laptop tricks I use that are less well known, but will help you deliver better presentations.
1. The Dual-Monitor Trick
You can set up your laptop so your presentation doesn't appear on the laptop you're presenting from, while your slides display normally onscreen. That leaves the laptop for other uses, such as displaying your notes.
The trick is to use Windows' dual-monitor mode. To set this up, connect your projector normally through your laptop's VGA port. Right click on the desktop and select "Properties," then the "Settings" tab. Configure this tab so your laptop screen is Display 1, and the projector is Display 2. Click OK.
Now, open your PowerPoint presentation, and choose "Set Up Show" from the "Slide Show" menu. In the "Multiple monitors" area, chose "Monitor 2" from the drop-down menu, then click OK.
Now run your presentation, and you'll see that your slides display normally, while your laptop is free to run anything you like, including a Word document with all the notes you want in giant type.
2. The Giant Clock Trick
Timing is everything when you're presenting. To always end on time without glancing at your watch (a gesture that communicates to the audience that you can't wait to finish and leave), place a laptop on the floor in front of where you're speaking, and set it up to display a giant clock.
You can do this either with a second, older laptop (or the notebook of a colleague), or use the trick above to put it on your laptop screen using the same system running PowerPoint.
The best clock I've found is a screensaver called the Text-Reader ScreenSaver, which is free. You can increase the size to take up your entire screen.
3. The Laptop Cue-Card Trick
I've worked with many speakers who always run way over their time (leaving less time for remaining speakers), and who are so focused on their presentation that they don't see colleagues in the back using sign language (pointing at watch, knife-hand across the throat, etc.) tell them to shut up and sit down.
One of the tricks I've used when presenting as part of a group is to use a two-laptop system to cue to the current speaker. You place one laptop on the floor in front of the speaker, which you control via remote-control software (an application usually used for tech support). I use an old copy of LapLink, but you can use any remote-control software.
This lets you use the clock screensaver to keep the speaker on track, but interrupt that clock with giant letters that say "Five Minutes" or "speak up!" or other stage direction.
Another related trick I use to get the attention of the speaker is that I set up the laptop with a black background. Then I have a full-screen instance of Word running but minimized, containing my message to the speaker. When I want to get the speakers attention, I hover the mouse pointer over the minimized icon on the Taskbar, and click repeatedly. This makes the laptop flash like a strobe a few times before I leave the message up, which I guarantee the speaker will notice.
It doesn't matter if you like presenting or hate it, whether you're nervous about it or not. If you're going to present, do it well. Don't kill them with PowerPoint -- knock 'em dead with a great presentation they won't forget.