Your best bet is probably to return to Windows 7 -- if, when you upgraded to Windows 10, you selected the options to allow you to 'restore' your computer back to Windows 7 ... AND ... it has been less than 30 days since you upgraded ... AND ... you have not intentionally (nor accidentally) deleted your Windows 7 files.
Four gigabytes of RAM is somewhat borderline for running Windows 10, regardless of what Microsoft says. Few people have a good time running Win10 on that amount of memory. There are lots of options & unnecessary built-in programs in Win10, but we can't tell you what to turn off as we don't know what is actually running on your specific PC. Every individual PC likely has a fairly unique mix of programs ... especially since you upgraded from Win7, because that means that all the old programs you used to have are (should be) still present and then all the new Win10 stuff is added on top of the old stuff and who knows what's actually running any more.
If you want to attempt to go back to Win7, here's a guide: http://www.howtogeek.com/220723/how-to-uninstall-windows-10-and-downgrade-to-windows-7-or-8.1/
If you want to muscle through and keep Win10, then perhaps you can respond with a list of what programs are generally running automatically -- right click in the task bar, select "task manager", in the 'task manager' window make sure you click on the link "more details" at the bottom of the window. Provide us a list of all the programs listed on the "startup" tab, and everything currently shown as running in the 'Apps' section of the 'Processes' tab. After you provide that info, then you may get some additional advice as to what you could or should try to disable.
Good Luck!
I have an HP PAVILLION computer with 4 gb ram. I just moved from Windows 7 after being told by Microsoft that I met the requirements. With only one app that I am working with I keep getting notices to save my work and close the app. (If I don't the computer locks up) I checked the task manager and ram is 65% utilized without any current apps open. I have only 4 apps in the start menu. Others have 5. I checked system resources and there pages of them that are running. At 85 years I don't want to install more ram. I only need basic apps...mail, a browser, my Microsoft Office 97 and few other such apps.
What system services can I safely delete or turn off ? Any suggestions are appreciated.

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