how can i fix my pc?

It looks like a failled install of Windows 7. It should not be a problem of hardware compatibility as Windows 7 is less demanding in this regard than Vista.
Maybe there was not enough free space on the drive to successfully complete the install process.

I do hope that you backed your data before the upgrade.

You have essentialy tree options:
1 - From the system recovery options screen, follow the prompts and any debugging instructions that may be offered.

2 - Do the system restore and hope for the best. If it's a factory state restore, it will erase all content of the disk and reinstall from an image from a hiden partition. It will also put back old and obsolete copies of any bundled softwares. You will need to uninstall of those.

3 - Try to install Windows 7 a second time. If you DO have a backup of your data, I suggest doing a clean install where you reformat the destination drive. Make sure that the destination drive have AT LEAST 50 Gb of free space. Having around 75 Gb or more is recomended.

Another option is to install a second hard drive and install on it. A new drive don't cost to much given it's capacity. This have the advantage of not affecting any data still on your actual drive.
The quality and reliability of the hard drives is essentialy independent of the price: A generic OEM no-name 1 Tb SATA 3 drive coming in a static bag is just as good and reliable as the most expencive 1 Tb SATA 3 drive in a nice fancy box from a big brand, and are possibly made on the same assembly line with the same standards and quality tests... So, you can safely get a prety cheap one.

You can't go back to a previous state using Windows check point.

In all cases you must make sure that your data are safe BEFORE you proceed.

If you don't already have a backup, I think that the Windows 7 DVD can be used as a Live CD.
Otherwise, get a Linux Live CD. You can have it from various sites as well as a torrent download. It come as an ISO file to be used to burn a CD-R. Some computer stores may also have those, normaly for free.
Unsing one or the other, copy all your importent data to an external drive or burn it to some DVD-R.
If you install a new drive, you don't need to backup your data. Your original drive can be disconnected during the installation process and reconnected after.

Electro
August 2011