If you have a restore/recovery disk and Master cd from your vendor for your type of computer and if you haven't changed any of the hardware since you bought it new, you should use those disk to do what you want...otherwise, follow the directions below (do the first couple of steps anyhow even if you do have the restore/recovery/Master disk setup).
FORMAT ONLY..FIRST RULE: BE PREPARED AHEAD OF TIME
Save to disk (floppy, zip drive, or cd if you have a cdrw) all files that you want to be able to restore later on. Email messages, address book, data you have personally created, zip downloads so you don't have to hunt for them again, mp3 files you may have downloaded, etc. Go through your C: drive folder by folder in Explorer to make sure you don't forget anything. Any programs you have installation disks don't worry about because you will have to reinstall them again anyhow. Make sure you have the correct info in Dial Up Networking for your ISP icon written down somewhere so you can get back on the net, too. NOTE: If you have a website, make sure you save that as well.
Do you have a bootdisk that gives you access to the cdrom in order to reinstall if your version comes on CD? If not, then follow the directions below (follow them anyhow even if you have floppy disks for your W95 and Office program)
Use the boot disk for the operating system you want to put on the harddrive (if you need one that gives you cdrom support go to http://www.bootdisk.com or www.bootdisk.de and download one now and make sure you get the right version for the windows that you will be putting on the harddrive and then extract that file to a temporary folder on your harddrive somewhere, read the readme file to know how to create the disk, then put a floppy disk into the drive and follow the instructions from the readme file to get your disk made. If you downloaded the bootdisk and it's an .exe file, you can just click it and it will start to create the bootdisk for you automatically. Also, when you use the bootdisk you downloaded, it will default to being the R: drive for the cdrom, but this is only temporary until you reach the windows desktop.
To check for your version windows, go to Control Panel\System and under your Registered Owner name, you will see some numbers. If the number is 4-00-950 with no letter or the letter "A" after it, you have W95A. If the number is 4-00-950 with a letter "B" or "C" after it, you have version W95B or W95C and will get the W95B bootdisk. If you have Win98 or WinME or Win2K or WinXP, this is an obvious choice for you from the site.
One last piece of advice regarding bootdisks before you format the drive.....go NOW to Add\Remove Programs\Startup Disk and create two more bootdisks (have your windows cd handy because it will ask for it). I've seen bootdisks go bad for no apparent reason when you least expect it, so make sure you have a couple of them handy just in case. Don't try to make a copy of the one you have using the A: drive copy command because the copy won't work at all since there are hidden and system files on it and they don't copy over....you have to make the new bootdisks from the Startup Disk tab. However, this will <B>NOT</B> work with W95 because the StartupDisk tab won't give you cdrom support so you will have to download a bootdisk for it instead.
NOTE: Although you don't need to use FDISK just to FORMAT the drive, I put this information here so that you will have it for your bootdisk for future use ahead of time.
Also, for W98, if you create the bootdisk from within windows, you will need to go here to download the newest version of FDISK.EXE then copy it to the bootdisk, allowing it to overwrite the older version. This way you will have support for larger harddrives.
FDISK LIMITATION WITH 64GB DRIVES:
Why does FDISK not recognize my disk (or RAID array) which is larger than 64GB?
There is a bug in Microsoft's FDISK under Windows 95B, 98 and 98SE that can be corrected by downloading a newer version. See Knowledge Base Article Q263044 for more information.