depends on her sexual preference; shows like Kyou Kara Maou, Skisho, Loveless are classified as BL (Boys Love = homosexual) anime if she swings that way.
Ai yori Aoshi, Kareshi Kanojo no Jijyo, Kimi ga Nozomu Eien, Kanon, D.C. Da Capo, Nanaka 6/17, Midori no Hibi are good romantic series you and her could both enjoy.. (not that i didnt like KKM tho, the show is quite amusing with sexual bias aside 😛)
For something cute and funny consider Galaxy Angel (series 1-4 and buncha OVAs), Digi Charat Nyo!, Azumanga Daiou, Sensei no Ojikan. many of the jokes in GA/Nyo are closely related to japanese culture / play on words so YMMV. personally i couldnt stop laughing for almost every second 😀
If she doesnt mind some fanservice material, something along the line of Mahoromatic (series 1-2 and few OVAs), 2x2=shinobuden, UFO Princess Valkyrie, Yumeria, Rizelmine, Stratos 4 and Daphne in the Brilliant Blue
Pitaten and Nanaka 6/17 are also good shows loaded with cuteness.
I thought Comic Party / Revolution / Special were very entertaining, she may like it if she is really into anime. Narue no Sekai certainly could use some more quality in terms of drawing and plot, but all in all show was good with some heartwarming episodes and excellent music.
Onegai Teacher / Twins were also great series in my book, complete with great humor, drawing, music, voice acting and everything. (I preferred the latter of the two)
Check if Uta-Kata is out on DVDs, it is one of best shows from last year hands down imo. Same goes for Rozen Maiden and Futakoi, some of other excellent picks from last year.
There are some really good recent series like Mahoraba, Gokujo Seitokai and Gakuen Alice, but I doubt they are available for purchase just yet.
I could recommend you more if it was just for you, but for girls excessive amount of fanservice could be a turnoff, plus I ruled out some shows that may be seen too dark, convoluted, pessimistic or mediocre.
Oh yeah, special honorary mention goes to Scrapped Princess, I have been listening to the soundtrack lately, reminiscing how good the anime was except for obvioulsy rushed ending. highly recommened for anyone.
Hope that would keep you busy for now 🙂