First of all, I will say this: if you install a new firmware/ custom firmware (2.00+), you will fix your problem instantly. Everything will work as it's supposed to. If you don't want to do that then I have an alternate solution, or at least one that I believe will work - which means it probably will
The second thing I will say is this: If you want to do things this way, use the usb connection mode in your recovery menu (if you have custom firmware) or pspfiler if you have a normal firmware to copy these files into the right directory.
It sounds like what you did was goof up your flash0 files. I believe you deleted them in order to make space? If so, you shouldn't have deleted the flash0 files for the web browser if you were going to use it!

. It would be great for you to be more informative so that we can help you further. We need more details like firmware, for instance.
If I'm right though, all you would need to do is get the flash0 files for the web browser from a clean dump of the firmware that you are using. So, for example, let's say you have version 3.00. If you DID delete your flash0 files for the web browser, you will need to download a firmware dump of firmware 3.00. The following files you would need, as well as their locations in the firmware, are as follows. Now I'm only 90 / 95% on this list though, so make sure to tell your firmware version to see if I need to look into it more.
In the flash0:/vsh/nodule, there are 3 files to copy to your firmware.
1. htmlviewer_plugin.prx
2. htmlviewer_ui.prx
3. htmlviewer_utility.prx
In the flash0:/vsh/resource, there are 6 files to copy to your firmware.
1. htmlviewer.fbm
2. htmlviewer.gim
3. htmlviewer.msg
4. htmlviewer.res
5. htmlviewer.snd
6. htmlviewer_plugin.rco.
-DarkPacMan77-