Proper storage, handling, and cleaning could mean the difference between warped, ruined records and a collection of which you can be proud. Treat your records well, and they'll last for a long, long time.
For basic cleaning, wipe records with a moist antistatic cloth. (If the cloth dries up, don't use it.) If your records are very dirty or moldy, use a moist cloth with a few drops of dish soap on it to gently clean the surfaces. Then run the record under lukewarm water, being careful not to get the label wet, and pat dry with a soft cloth.
The jury's still out on whether or not alcohol will harm your records. Some sources say never use it, while others claim it's perfectly safe, if the concentration is no more than 70% (i.e., rubbing alcohol). The choice is yoursbut you may not want to try it out on that $10,000 Dylan LP.
Consider purchasing a record cleaning machine. You can find them for less than $200.