For all you PSP experts out there..?

I got a question. I want to do homebrew for my PSP, but it's impossible, as mine is the old PSP 1000, and I updated it to 5.51. So I was wondering, if I get an empty UMD disc, or unpatched or whatever, and put files of games there, will the game work straight away on my PSP? Even though it's 5.51?