My laptop is 10 years old with original windows vista (CD) .
Toshiba , 2 GB RAM .
No viruses no malware.....
always updated and has anti virus too.
But that is very slow, specially when I run browser. ?
Run something like SuperAntiSpyware and see if it picks up anything. It's pretty good at snagging junky programs that might be slowing you down. 4GB of RAM is advised too, although I'd suggest a new laptop entirely.
You need to backup your comments with some sort of reasoning. Advising somebody to install XP in 2016 is downright foolish except for very certain usages. Especially as a downgrade from Vista.