1. If I were to host a TTT server 32 slots and a lot of addons what CPU would I need?
  2. How much Ram would the server above probably use?
  3. How much ram would my forum and servers sql database use (medium size of data)?
  4. What types of addons in TTT are the big offenders for lag?

depends on the addons honestly but any old cpu could probably run it providing there is nothing else going on in the background.

2gb of ram is recommended but the server should use no more than 300mb of ram realistically.

anything ragdoll related will cause lag for the network try to avoid those or huge bombs that will kill everyone at the same time these can be quite bad depending on the code.

Hope this helps.