@GG: Up until last year I used older PC's all time and it's made me a bit of an expert at squeezing everything out of a computer I can.
First, I think it's important to understand there's only so much optimizing you can do before you just can't do anything more for it. My grandpa is stuck on the train of thought that if he takes care of it and cleans it constantly that it will last forever. I think it's because he grew up in the aftermath of the depression and it's just stuck with him. I mean come on, he saves the springs from ballpoint pens and puts them in a jar because he thinks he'll use them (I'm not joking). He just tries to make things last beyond what they are capable of. I guess there's no harm in trying.
Hardware get's old and software get's newer. The reason we buy new hardware is because the demands of the software increase so we need something faster or something than can hold more data. My point is that if your PC really is as old as you say it is (and why we held a fundraiser for you), then no amount of optimization is going to breath new life into it like it had when you first bought it.
Having said that, I'd try the following.
If you have XP or Vista on it, change the appearance back to that of window's 98.
Turn off all folder special effects.
If you have a lot of start up programs that run in the background, only load the ones you absolutely need in at start up. Launch the rest manually and only run them when you need to. If your not using it, don't have it running in the background.
Decrease your resolution.
Defrag your hard drive every week. If you install a large program, transfer large files, or uninstall large programs or delete large files, chances are there's gaps in your hard drive. Defrag will help put all program files together and close the gaps in between them. This speeds up the read/write speed. I recommend Auslogics Disk Defrag. There's nothing like getting an 11% boost on hard drive speed like I did last night
Registry cleaning is optional IMO. I don't think it speeds up your computer as much as it does prevent residue. Careful cleaning it. CCleaner's reg editor has never done me wrong. Be sure to back it up just in case.
Be sure to scan for malware often. You don't want a bunch of unauthorized programs leeching off of you.
Be sure to get a quality anti-virus scanner, but try and find one that is lightweight (meaning it doesn't take up a ton of processing power to run in the background).
"If I have seen a little further it is by standing on the shoulders of Giants" - Isaac Newton
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