I wouldn't trust anything from a P2P site that purports to be:

1. A cracked game / application for desktop and mobile platforms. Maybe it's legit but assume it is malware.
2. A serial number generator. If you absolutely must run one of these do it from a throwaway VM, or via WINE emulation to mitigate what it might do.
3. An encrypted archive with a README. It's a scam designed to make people sign up to other scams to release a non-existent password.
4. A movie / audio with an extension such as .scr, .wma, .com, .exe etc. It's malware.

Movies, audio & books are generally safe providing they use a recognized extension - mp3, mp4, pdf, mkv, aac, flac, epub etc. Stuff that runs under emulation like console games is generally safe. I say "generally" because an exploit could still be crafted to escape a popular media player or emulator and cause actual harm to your computer.

All the ads and 3rd party scripts should be considered malicious too and should be erased with an adblocker, or even better use Tor.

So basically use some common sense and if you really want some game or app, just buy the damned thing or wait for it to go on sale.