|Where is the difference?|
You had WinXP 32 bit and can use Win7 32 bit.
The browser only, isn't the the problem.
If WinXP has a security hole, which will never be fixed in the future, it's a matter of time, to get infected or hacked.
And, btw, Win7 is a good OS. With some small tools, it looks like WinXP and on my experience, it more stable than XP.
Windows 8 is not my thing.
It's as it always was. Every good and stable Windows version is followed by a bad version. So while Win7 is a good one, you can guess, what Win8/8.1 is.
Version 9 might again be a good one, hopefully.