If you have to ask the question, then chances are that you will be perfectly happy with the Home Premium edition of Windows 7. This OS is the cheapest consumer edition of Windows 7 and includes everything that the average user will need.
If you think that you might need something extra thats not included as part of Home Premium, then there are the Professional and Ultimate editions.
The differences between the editions are subtle. To determine whats best for you I recommend that you take a look at the editions chart over on the Microsoft website.
Dont panic! There are two options open to you:
First, you can use Microsofts Anytime Upgrade feature that allows you to purchase a higher edition. This is a quick 10-minute process and prices are reasonable.
You might be able to add the feature you are looking for using third-party software. In fact, theres almost no feature that you cant add using third-party software.
If your hardware can handle it, theres essentially nothing preventing you from going 64-bit and being able to break the 4GB memory limit that has plagued the 32-bit operating system.
If you have any doubt about your hardware, consult the Windows 7 Upgrade Advisor from Microsoft.
Believe it or not, I suggest that you copy the files off the DVD onto a USB key if you have one thats big enough and install from that.
Why? Because its faster than messing about with the DVD. If you have more than one PC to upgrade, then the minutes that you save start adding up. Not only that, but after copying the files to a USB key you can put the DVD disc away for safe keeping.
First, get all your hardware working right. After that, install all your must-have software. Then, make a backup of your system and store this safely on an external drive if you have one. Dont have one? Get one!
Why make a backup? Because when it comes time to reinstall youll have a nice, clean image of your system that you roll onto your PC in a matter of minutes, if things go wrong. Its an additional hassle at the beginning, but when you need that image, youll thank yourself that you did it!
Note: Windows 7 hits stores October 22nd!