Referral sites are where you refer friends to the website, and they generally (95% of the time) have to complete an offer to count (or go "green")
Recommendation would be any Trainn websites, honestly. Depends on what your interested in, these generally require Credit Cards, and the Trainn network is found here:
http://www.trainn.org/ .. Sample sites include:
Nintendo Wii and
Free 360 Games.
Surveys and offers sites are just websites that you have to complete on your own, you can also refer friends to some of these websites to also receive a bonus such as some sites offer 10% of what your referals would receive (that is on top of what they receive, so you aren't taking a percentage from them).
Recommendations here would easily be
CashCrate,
MyFaveFreebies, and
PrizeRebel. with CashChute and
Cash Lagoon /
Gaming Lagoon behind those.
Search and wins are generally just searching like Google, with a chance to win something like Amazon GCs or movie tickets .. just a search engine with a prize.
Either Big Devil (
link), Winzy (
link) would be my recommendations here, both are handy.
And the games, are just games .. chance games with chances to win cash or other prizes.
Moola (invites here:
link),
Netwinner are the only ones I know of for "chance games".
Any other questions, feel free to ask away .. I'm sure someone can answer them.