Assuming you keep your virus protection up-to-date, you may not have a fatal virus, but you could have some files that came from your downloads that latch on to things and create the problems you are experiencing. You could also be sending these files to others while not malicious create problems. If you have a windows based machine, you could perform a reset to a date before the problems started or even scrub your machine completely and start over. The worst is you have several viruses though if you are still running that may not be fatal, but I would act fast.

OK I have a memory that there's a technical section here - but I can't access it. That's part of my problem.

Recently I've downloaded a few PDFs that have nothing to do with my Tamara world. but suddenly it takes FOREVER for me to dowbload just about anything. I don't want to delet any of these programs, but I sure as hell need some speed on my laptop - any ideas?

Tamara xxx

I put that on my computer, and if ever I get some attack virus from some porn site, I just shut down, reopen in safe mode (Did everyone but me know about that F8 shit?) and run the Malwarebytes.  A few minutes later, the virus is gone and I'm good to go.

It's free.
It will clean the hard drive, and it has a registry cleaner as well. It gives you the option to backup the registry (which you want to do) before it fixes it.
After you run the cleaner, fix the registry, run the cleaner again, then de-frag the drive.

It should run almost like new.

to keep your system clean.

Nothing will slow down your system more than that, as long as your anti-virus program is up to date.
Never run more than one anti-virus program at a time. They will cancel each other out.

FileHippo.com is a safe and easy site to download free software.

Also try CCleaner, another excellent program you should have to keep your system clean.

Good Luck

How old is your PC? Eventually all PC's slow down due to registry corruption. The best potion is to back up your stuff and re-install OS.

Not joking by the way.