Hi Sara
being an engineer myself i too have used what you call the Pc. what you real mean is you have been using te Microsoft software which is full of bugs and other irritations such as viruses.
well yes they do as you say get slower and slower as time passes.
There has always been an alternative in your lifetime that has been UNIX which has been around since the 1960's. but it will only easily run on a apple Macintosh computer.
there was a very clever dutch man linus who in the 1990's managed to port unix to the intel and amd processors used in what you call the PC.
so what is the the PC it is a computer it has no preferences to Microsoft at all it is just a computer.
This is a common mistake made by many.
you can load what you like or should be able to but as Microsoft did some deals with some manufactures over the years some have been difficult to load anything but the awful Microsoft software rubbish.
Now apple have also switch over to the Intel processors so we now have a much more stable operating system running on dual core and multicore processors with out all the horrors of what Microsoft has caused to happen to some good hardware.
that is enough of the knocking but here is the truth.
by using Intel processors with unix we have a much faster and use able operating platform which has virtually no problem with a virus as it is a structured system.
It has proved itself in the fields of business and home use especially in the areas which you are interested in, Auto cad And art and design and many engineers swear by them as they give faultless operation when compared to anything microsoft.
I KNOW THIS SOUNDS LIKE A SALES PITCH.
but like you i have been with the Microsoft problem now for some 17 years and it does not get better in fact it gets worse in my humble opinion.
i have only found apple in the last 9 months and i am kicking myself for not trying it years ago.
having worked on unix mainframes in the past as a systems manager with a large corporation it was always so much simpler before bill gates arrived.
So you want speed and reliability well you will get it without the virus hassle with Mac book pro.