Zelda, for two reasons. First: the many things that make her awesome (beloved ruler, indicating wisdom; magic power; the ability to flawlessly balance being a strong and independent woman with still needing help all of the time; etc.) Second: if Zelda is in love with me, I'm probably about to turn into a hero prophesied throughout the ages.
Our relationship would start when the entire world is in jeopardy and she needs help, and would end after a long and otherwise uneventful happy life together with a mysterious case of global amnesia that rearranges the world and causes me to be replaced with someone who looks exactly like me and has the same name, ready to deal with the next threat.
Runners-up include:
Samus (she's hot, but my only experience with her is from Smash Bros so I know nothing of her personality)
Rebbecca (Fire Emblem - she's my dream girl, but I couldn't bear to break up her and Lowen)
Jaina Proudmoore (Warcraft - I'd be too nervous about being hit by the continual apocalyptic tragedy that constantly afflicts her)