I bought a Lenovo G700 laptop almost brand new that came with Windows 8 pre-installed but whose previous owner installed Windows 7 Home Premium on it.

When I EXAMINED that laptop I found two for me estrange things:
1.    There is a 100 MB partition, with 60 MG used only and without letter.
2.    Instead of primary and logical partitions, its 500 GB disk has SIMPLE volumes. That is, it's a dynamic disk; first time I see that.

I've read a lot about and LEARNED that the 100 MB partition is required for recovering operating system, something that my desktop, where I installed Windows 7 upgrading from XP one year ago, has not. And I also learned that dynamic disks are better than basic ones, but for reasons I don't understand and I don't plan to use. I PREFER to keep using basic disks and primary/logical partitions.

Since I already got very familiar with the Windows 7 installed in my desktop, I want to get the laptop as much equal to my desktop as possible. In order to achieve that I need to convert dynamic disk into basic, so that I can make System Image using 'EaseUS Todo Backup', and I can manage partitions using 'EaseUS Partition Master' like I've done for years.

However, for reasons I ignore, sometimes that laptop takes about 3 minutes to start up, and I suspect that
•    Something was wrong when Windows 7 was installed instead or on top of Windows 8, and that,
•    Maybe, partition in point 1 above is good to recover Windows 8 only but USELESS with Windows 7. I just changed its letter —it had a hidden E and I changed to Z— and nothing changed in the laptop operation; so I put back the E letter.

So, if something goes wrong when changing dynamic to basic, I'd like to format the disk and proceed to make a Windows 7 fresh installation, but I have some questions about.

1.    What program, resident in an external media —CD or pendrive—, could I use to format the disk?
2.    Should I keep the supposed recovery partition? I repeat: In my desktop I upgraded from XP to Windows 7, and disks remained basic, and no recovering partition was created.
Sounds like quite the mess.

As far as changing partition types this is generally handled by default by the installation ROUTINES of the OS Disc when installing to a bare HDD or SSD.

Two suggestions I have are the following after backing up any important data you may have on this system:

#1 - If you want Windows 7 to run clean on this correctly, I would use a program such as jellybean to figure out the key that was activated for this Windows 7 install and write down the key. Then use the Windows 7 installation disc or an XP installation disc and boot off of it and at a point in this process it will allow for you to delete partitions that are detected and it will show details about the partitions. After deleting all partitions, if using Windows XP disc to delete partitions, you can remove the disc and then place the Windows 7 disc into the drive, and then hold the power button to force shutdown of the system. Next boot the system up and boot off of the Windows 7 disc and perform a clean install. Windows 7 will build the necessary partitions clean. When done with Windows 7 install you will have the key to activate with from what jellybean provided for you. *As long as this is a legit key and it hasnt been activated too many times or flagged as a pirated key it should activate with no problems.  (**** Another method of partition deletions is to use a bootable Linux disc to wipe the partitions and make the drive bare... but its best to use XP or 7 bootable original OS disc instead of the Linux method, especially if your not familiar with Linux. )

#2 - Contact the manufacturer of the laptop to obtain the system recovery media for some day when you want to install Windows 8 to it. This might come at a charge of around $35. ( * Do not tell them that this computer is second hand, tell them that you are the original owner.... have experienced issues with ownership that was not original ownership and had to place a second call with a different support specialist and lie to state that I was the original owner when asked  to get the media I needed and still had to pay $35 for )