if you run win XP, use the system restore tool to roll your system back to a time when everything worked properly.
If you dont use Win Xp you can do this manually by just checking all files modified before a certain date. If the problems just come up its probably something recent youve downlodaded/changed thats causing the problems.
Also consider getting some anti,viral, anti adware and spybot removal programs if you havent got them already. Im sure some of the tech gurus here could give you better advice on which are decent, but personally I find Spybot- Search and Destroy, Adaware Pro, Avast Antivirus and a Zonealarm Firewall more than adequate for a home PC.
It could be something as simple as a download thats corrupted some files causing your driver information to change that would explain why its causing UI error as logically that would suggest an issue with your graphics drivers or settings to me. So you can try see if you still have all the latest drivers for your hardware and reset the settings of JA to default by un-installing and re-installing it.
As to hitting machinery to make it work.... dumn idea unless you can afford to buy a new one and it only is ever a short term fix as such actions will cause more problems in the long term. If all of the above doesnt work... then formatting and doing your PC from scratch will more than likly fix the problem just make sure you back up any data you want to keep.