|What is the 3% figure? 193MB is almost certainly RAM, which is a fixed size and can only be increased by replacement. We need to be quite sure what you mean but I will assume, for now, that you are trying to reduce RAM usage.|
Memory (RAM) is totally different from "hard disk space" (see EDIT later). Removing files and programs will not help performance at all unless they are active and constantly running in the background.
Have a look at what is showing in the taskbar next to the clock - these are all running programs. If there is anything there you don't need then use a proper uninstall (from Control Panel Add-Remove, or any provided uninstall).
After that If you type msconfig in the Run box, hit Enter key and look in the Startup tab there might be some things there you can disable from startup by unticking them.
If you are looking to free up hard disk space then this is a completely different matter, but you usually start by "properly" uninstalling unwanted programs. It is also fine to delete unwanted files and folders "that you put in individually yourself". Otherwise be careful deleting files and folders, this nearly always leads to disasters.
What is your HD size and how much free space do you have (right click C drive and go to Properties)? The file sizes listed are unlikely to have much impact on hard disk space.
Purely for info, Memory (RAM) is fast and acts as a working space for the processor (CPU) to use. It copies info from the hard disk but is emptied when you reboot. If it is too small performance will be poor. The hard disk is much slower and is used as bulk storage space for programs and data.
We all live on the same ball.