If your running Windows 7 and the glitchs are mostly software (as opposed to hardware) you may try a software reboot:
Depending on the manufacture of the laptop, you may be able to perform a 'reset to factory condition'. This option deletes everything and resets the laptop (or desktop, it works for either) to the exact same condition as when you pulled it out of it's box fresh from the store.
NOTE: This will format the hard-drive and put the original image file of the computer back on the hard drive. This WILL DELETE EVERYTHING so backup all data, program serial numbers, website favorites, passwords, etc. YOU WILL LOSE IT ALL!! But if the issue is because of bloated software, this will fix. You will have to install all software again (but you would have to do that on a new computer anyway).
I typically see a 100% performance increase when I do this (about once a year--unless I feel lazy
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