What are you interested in? If you give some more information it will be easier to get some answers.
Please note that if you are a resident of the UK you need an Interrail pass and not a Eurail pass.
This site has all the info for ignorant (about train travels ´on the continent´) people: seat61.com
Lists all easily accessible routes, gives all info on tickets (NOT speciific for passes!) for all countries in EUR. Start there-then think wbout what you would like and if any specific Questions remain-come back
OR just browse this forum to get a feel for what probs tipical train-newbees usually encounter-they gat asked daily.