Neemobeer,
Many thanks for your prompt reply and your advice. It is much appreciated.
My Vista version is OEM. I do not know if I was given the original Install disc. If so, I'm not sure if I can find it, and therefore I do not know if I can do a reload. I can certainly try to clean the laptop. The reason I mentioned Win 7 is because I am very pleased with my experience on my other laptop, and I have read that Win 7 runs faster and more efficiently than Vista. I really don't mind having Win 7 for 2 more years (until 2020), and then maybe choosing something else, but of course there's the question of the cost for another Win 7 copy.
I do think the hardware is low-end. I am running a Compaq Presario CQ60-210US laptop, AMD Athlon Dual Core QL-62 Processor at 2 GHZ, with 4 GB RAM. I have Vista Home Premium; I guess that the machine and the Win 7 version are both 32-Bit based (sorry if I'm saying something obvious).
It's interesting that you mention Linux. I don't mind giving it a shot. Per your opinion, could Linux Mint -- once installed on the older machine -- run faster and more efficiently than the current Vista setup that I have now?
Again, many thanks. I very eager to get your feedback.