*disclaimer* in all my years of teching, these never broke anything worse than it was already broken.. that being said, always back up your important stuff before you start banging away at your PC.
Here are some things you can do to speed it up... this is basically a shotgun of manual windows cleanup and whatnot. This wont reset anything, it just cleans house. Windows is supposed to do its own cleanups, but a lot of the time, stuff gets jammed or corrupted and stops it. This will kinda reset those things but without having to re-install anything. I find that if a pc is quirky and slow.. the chkdsk /f really help.. it is the yellow pages of whats on the drive and if some of those pages gets jacked, it can cause pc slowness bigtime.
all these scans are built into windows.
1. start cmd prompt as admin and run chkdsk /f then reboot. 5-10min
2. go to c:\windows\temp and delete the contents
3. go to c:\users\wifesname\AppData\Local\Temp and delete the contents (this is a hidden folder, so check show hidden folders)
4. go to c:\Windows\SoftwareDistribution\Download and delete the contents (this is where windows updates are downloaded and installed from.. clearing it out might get rid of some update that might keep trying to install and is looping and using up system resources. one emptied, it will repopulate as needed when it runs updates)
5. go to cmd prompt as administrator and run sfc /scannow 5-15min and if you get "corrupt files found and cannot be repaired" RUN IT AGAIN... up to 4x.. as sometimes when it fixes one thing it opens the door to other broken things that will be repaired on the next run. (this is system file checker, it checks the system files of windows against the originals in a library file and repairs corrupt ones)
Also.. how full is the hard drive?
Once that is all done.. go to Acer site and download the latest drives for specific model and install. Especially the graphics driver.
As for the battery.. do it yourself. It will probably take you longer to unscrew the screws on the bottom than to actually swap out the battery. There are probably 15 YouTube videos on how to do it for that specific model. Ifixit website also is a great resource of how-to's