Sure you can (go back to Win7) and yes you should!
Any computer that is currently available will run Windows 7 just fine, and there will be Windows 7 drivers for all of its devices, even if the PC manufacturer doesn't offer them on its website.
First, you will need to buy Windows 7. You could buy a full-priced retail version (more than $200 plus tax) at a local store, but the OEM system builder version is best (and much more economical). You can buy this from websites such as Newegg.com. The Home Premium version costs less than $100, and is available in 32-bit or 64-bit versions. For a new PC, go with the 64-bit version.
Second, go into the Device Manager and write down the brand and name of each device in your system, i.e. the graphics chip, memory card reader, touchpad, audio chip, wireless card, LAN chip, etc. You will need this information to download suitable Windows 7 drivers, which you should download and save to a flash drive BEFORE you install Windows 7.
Third, use a program such as killdisk to do a zero-fill of the hard drive, eliminating the "recovery partition" and other garbage, along with the primary partition with Windows 8 installed.
Fourth, use your new OEM Windows 7 disk to load Windows 7.
Finally, install the drivers, and run Windows Update.