you never said what you are using media player for. Music, movies. Personally, I do not like wmp . I do not like media monkey because it is very unstable. i also do not like winamp. For a stable media player try J River Media 12. It is easy to use for the newbie, or very complex for the advanced users. Another good one to have is Media Player Classic. In the past media players were loaded with undesirable software( spyware). Not sure if that is still the case, but some players are nothing but a total hassle.
Another thing to considered, you should back up all your data, computers can just crash, and you could lose some data.