I have dell inspiron 531s. when trying to load bios or get to the boot menu they load and then automatically shut down and start to load windows. Then windows doesn't load. I want to do a system restore.

SOURCE: How to play movies from computer on tv?

if your tv has vga in, then you need a vga to vga cable (like a screen wire) then change the resolution in the settings of windows (put 800X640 resolution before you plug tv so that you can know what is supported)

if it doesent then you cant do anything other than buying a video card with hdmi or dvi (with a dvi to hdmi) with a hdmi cable then plug it in (will auto detect)

SOURCE: dell inspiron 531s

Download your manual for here. It usually has pictues to show how to open the case. 
http://support.dell.com/support/topics/global.aspx/support/product_support/product_support_central?SystemID=INSP_DSKTP_D531

SOURCE: Dell Inspiron 531s Windows Vista

If you are given the option to go into the setup (F2) try to disable the floppy disk drive or move the hard drive up in the boot order.

SOURCE: my desktop dell 531s is running extremely slow

Go to bios option and optimized default configuration specially in boot option.This should cure it.Dont forget to Change the DMA to disable and the transfer mode to normal.

SOURCE: my dell ispiron 531s will boot up but stops right be for desktop

Reformat your computer this shouls cure the problem.