First things first, if you could let us know what version of Windows (and what service packs) you have installed, we would be able to narrow down the problems, and help you in a more specific way.
As I am sure you are aware of, slow downs in Windows can be caused by many things. Before we get started on fixing the problem, it would be beneficial if you could state whether or not you have scanned for Virii, Spyware/adware, defragmented your Hard Drive(s), and checked to make sure that you have sufficient free space on your primary drive, and all other partitions. Also, please make sure that you update all of these, as new threats to virii and spyware come out daily.
After you have done all of this, and if things are still slow and/or crashing, there are a few other things that you could take a look at. One of these things is the amount of programs running in the background. To check this, download a program called
--CodeStuff Starter--, install it, and see what you have starting at start up. After doing this, and doing some research on what processes are running, get rid of the ones that you do not use or have a need for. This should help with boot up times, and with overall system performance.
Next you might want to try a hard disk check, just to make sure that there isn't anything wrong with it physically. To do this, go to
--This Thread--, download the appropriate tool for the Hard Drive that you own, install the utility and run it to see if it comes up with anything. This will tell you if you need to send in your Hard Drive for repair/get a new one because it is at the end of its life.
Chances are that your unexpected program shutdowns are due to data corruption. It might be possible that your system was recently unexpectadely shut down, and some of your files could have been corrupted. This would cause programs to fail, and performance to dwindle. To fix this, you would have to do either a repair, or a reformat (depending on your version of Windows).
Below are a few other sites that you might want to visit concerning Windows slowdowns. You might find something that could relate to your problem.
There are also other factors that could cause your system to slow down, but they are less likely to happen. These have to do with faulty RAM, unstable overclock causing corruption, power spikes, degrading components etc., but before we even consider that (as a lot of detail is still needed), we must get past the obvious, as chances are, those are slowing down your machine.
If you have any more questions, or if nothing that I mentioned has helped, please, dont hesitate to ask for more help, as I, along with others, would be me than happy to help you out.
Raven