I don't have much time to type this, so i better hurry. Ok, my computer stops responding so often now that the computer won't go past the sartup screen. like, right now it could freeze. It's really annoying cause there are violent episodes of freezing, and periods of normal function(like now). what could it be that's causing this?
When does it happen? All the time, or during specific periods (say, boot process, after login, while using a particular application or set of applications)... Does the computer ever recover from the frozen state, or does it have to be rebooted? Does it display any error messages, or reboot by itself without your intervention? If it happens all the time and independently of what the computer is doing, there are chances of a faulty memory module, which might require replacement, or power supply issues.
it happens randomly, like before booting to surfing the web. it has to be rebooted. sometimes it reboots itself.
Then yeah, I'd say memory problems or a faulty power supply. You probably need to take it somewhere... It would be useful if you had an Ubuntu Linux CD... they come with a memory test program which would be useful to identify memory problems.