Personally my preference is Firefox, and my secondary browser is Opera. I used IE9 for 2 days and can not stand it as it does not do what I want.
This extension can help you set custom zoom sizes on Chrome: ZoomAll
To resolve the speed, try updating drivers
, clear history, cache, update flash/java, etc (or even updating Chrome).
CCleaner or Disk Cleanup can help do a portion of cleaning.
Since it is new, you could try checking for updates on Windows Update.