Which is better for an older computer? Vista or Windows 7?

Which is better for an older computer? Vista or Windows 7? I've got a Pentium 4 3Ghz with 1.5GB of RAM and onboard graphics. Vista seems to be a little much for this old of a computer. Would Windows 7 handle the system better?

I know Windows 7 is better in many ways, but would I actually notice a difference in this scenario. How would XP compare to 7 in terms of older computers?

I have a similar system at the moment; P4 3.0GHz and 1GB RAM. Runs XP fine for me bearing in mind I have done a lot of tweaking and keep things very streamlined etc. If you have XP I would stick with that...Vista and 7 would likely both struggle.

I think the best thing you can do, if possible, is upgrade the memory. 2 x 2 GB should help the system run a lot smoother and take advantage of the hypertrheading, and not cost too much. Note that computer will only be able to use about 3.2 GB of the memory - but that is still double what you have. What memory configuration do you have now? If it includes 2 sticks of 500MB, and you have 4 memory slots, you might also keep those two and just add 2 x 1GB.

By the way - are you sure hyperthreading is turned on. When you open Task Manager and look on the "Performance Tab" do you see graphs for two CPU Usage Histories? I have a Dell with P4 3GHz and found I have been using it for years with hyperthreading disabled. I only learned this after reading about a post that said some systems had shipped with it disabled. Anyway, speed on some things improved after I went into the BIOS and enabled it.