Windows 7 Clean install Guides: this is by far the best way to install Windows, doing it this way means there will be no previous baggage present on the hard drive to hinder its performance.

An upgrade install (For Example) to a new operating system will have without doubt many stray files, drivers, and registry entries that do not belong to (Or are compatible with) the new operating system. Many times I have seen upgrades go drastically wrong due to these problems, causing great disappointment to the person involved. So to sum up, if at all possible do a clean fresh install on a new hard drive, this will give your computer a jump start in the world with it bright a shinny new Windows 7 Operating System.

Windows 7 Reinstall Guides: A reinstall guide is the replacement of an already present operating system. So if you wish to format your hard drive and put Windows 7 onto this drive then the reinstall guide is for you. Same as a clean install but with the removal all traces of the previous operating system. You can use this guide also for replacing an older Windows with new. Lets say you have XP , and now wish to replace this with Windows 7 using the same hard drive, then these guides are for you. The reinstalling Windows Help on this site is probably why most people come here.

Windows 7 Parallel install Guides: What's this all about I hear you ask (Well probably not), well a parallel install guide is when you take your new operating system (or Old one if you are doing a data recovery exercise) and install it along side an already present operating system, in theory you can run as many operating systems as you wish as long as you have the hard drive space. Its very good  for uses like data recovery, testing a new operating system, or to keep your old operating system in place will you migrate to new (As I always do), plus if you parallel install and find Windows 7 doesn't like your favourite piece of software, then you can simply boot into say XP and work with it there. On my desktop computer I run XP home, XP Pro, Windows Vista 64 bit and now Windows 7 64 bit. Each Operating system has its own independent hard drive (You can use partitions if you wish, but its not recommended). This best way to do this is to install the oldest operating system first, and then parallel install in order of age, finishing with the newest. There is other ways of doing this but this is not the place to go into such depth.

Windows 7 Repair Guides - One of the main reasons most people wish to reinstall windows is due to startup problems and errors within the operating system. For this reason Microsoft have included some repair options to assist you when times are not looking so good. To access the repair options you must boot of your Windows 7 DVD (Some companies like Dell, HP, Compaq etc etc will have the repair options only available through the "F8" menu that is available on boot, (as they do not supply a DVD), this is complete useless if your computer will not boot. There is light though at the end of the tunnel, if you can download a Win7 DVD or borrow one then you can use it too, you will have a unique Microsoft serial Number on your Computer somewhere. Its you COA (certificate of Authenticity) See here for more information on COA's.

Back onto the available Repair options. The following is available to you: "Startup Repair" (For when your computer will not boot), "System Restore" (If a problem only started recently then use this to time warp your computer back to a previous state (Say a week earlier) and all should be cured, "System image Recovery" (Restore a backup, if you have one....), "Memory Diagnostics" (Use for random crashes and system erratic behaviour), and last but not least "Command Prompt" (Only use if you know what your doing, this is a manual repair and fixes station, (a wrong command could erase your computer)).

Many useful options as you may agree, always worth a try before formatting your system. A virus scan with up to date software ( AVG Free is a good piece of software) and the same with a good Spyware program (Ad-Aware is another nice piece of software (And is also available free of charge). You may agree that these few steps are worth trying before making any drastic steps that would require a full reinstall of Windows/Drivers/Software/Emails etc etc.