I would do it myself. The learning experience itself is worth more than that. You will know enough to be able to repair and/or reinstall your OS at any time in the future and become very popular with your friends (mine fly me all over the world
See if you can boot into Safe Mode with Networking
by tapping F8 at bootup to access Advanced Boot Options
. Install, update and run Malwarebytes
full scan. If you can't boot into Safe Mode, download and burn to CD a free bootable AV scan to boot to scan your HD: FREE Bootable AntiVirus Rescue CDs Download List How to Boot your Computer from a Bootable CD or DVD - Boot to CD
Next you need to borrow, find or download the Windows 7 Installer ISO for your version, which can also be used for Repairs. We are not allowed to link to the ISO downloads here as it is thought to encourage piracy, but you can search for Official Windows 7 Downloads at My Digital Life yourself. Download and burn to DVD or write to flash stick using this tool: Windows 7 USB-DVD Download Tool
As an alternative you can make a Windows 7 REpair CD from another Windows 7 computer: System Repair Disc - Create
Now boot the DVD Repair console or Repair CD, See if it finds an installation to repair, accept any offered Repair. If Windows 7 doesn't start, boot back in to run Startup Repair repeatedly from the Repair console's System Recovery Options.
Report back here what it finds.
You can copy out your files using the Install DVD: Copy & Paste - in Windows Recovery Console
or Paragon Rescue CD freeware.
If repairs fail you can run Full Factory Recovery from its partition at boot using F9 key, run Recovery Disks if you made them, or boot the Windows 7 Installation DVD to clean reinstall with the Product Key on COA sticker following these tips to get a perfect reinstall: Reinstalling Windows 7