Make a Necromancer
and an Elementalist. As secondary profession, i suggest you to choose /Monk for the hard res. Don't warry about complimenting your primary with secondary skills when you are in low-level areas, only primary skills do just fine with both professions. When you reach level 20 and you unlock all seconday professions you can start thinking about efficient builds which rely on sinergy between primary and secondary profs, but at the beginning just don't worry about it.
If you are interested in good builds for both professions and general guidelines on how to play them, you can find some interesting guide in the Campfire section of this forum
http://www.guildwarsguru.com/forum/e...list-f205.html
http://www.guildwarsguru.com/forum/n...ncer-f208.html
For PvP, wait until you have unlocked several skills, armor's upgrades (runes & insignias) and weapons' upgrades in PvE, then start choosing simple builds in PvXWiki
http://pvx.wikia.com/wiki/Category:G...king_RA_builds
and try them out in Random Arenas (or Alliance Battles if you have 3 friends or if you are willing to PuG). The most important thing in PvP is NOT the build, but knowing the different techniques (which apply to all builds), so you can just pick up a good build and learn how to play using it.
Make a PvP only char for doing PvP, and start unlocking items as soon as you make enough Balthazar Factions. Very Important Items are Superior Vigor Rune, HP+30 for shield, 20% Ench staff wrapping (useful for your elementalist), 20% HCT and 20% HSR of item's attribute for wands, focus, and inscriptions.
If you want PvP to be an exciting experience, be prepared to read a lot (you can find a lot of useful guides in this forum, but even more simple threads all around it, so learn to use the Search function and use it a lot) and to practice more. It will be difficult and probably a little frustrating (mostly in RA) the first times, but as you grow in skill you will have a lot of fun.
Finally, it's really, really, really advisable that you find a guild (the best would be a PvP-dedicated guild willing to teach newbies) and build a strong friend list if you want to go beyond RA and AB pugging.
Hope that helped