Reading the description carefully will help you - try a few mods and see how they feel in your game. You do need to make sure that the mods are updated for the latest patch and you have the appropriate game packs. They won't kill your game, but you may want to quarantine your "script" mods in a separate folder inside your mods folder - if you have any issues, start by pulling the script mods and see if your game goes back to "normal". In general, having multiple mods doing the same thing is what is going to give you a problem.
If you are super concerned, you can create a notepad file, copy the xml's used in the descritiption and the name of the mod, and keep track that way.
LittleMsSam's
http://littlemssam.de/ mods are great, and so are Coolspear's
http://simsasylum.com/tfm/index.php...-mods-and-lots/ mods from simsasylum.com/tfm/ are awesome.
Have fun- try it out!!