Is this building an example of Islamic Architecture? (The exterior mainly) Type in Notre Dame de Fontevraud on ya hoo and it should be the first link for pictures of it.

No, it's not Islamic architecture.

http://www.sacred-destinations.com/france/fontevraud-abbey

Is the Castello di Chatelard an example of Early Christian Archiecture?

I don't think so. A castle isn't usually of Christian architecture. In addition, this building is later than what's considered early Christian.

http://www.pitt.edu/~tokerism/0040/syl/christian.html

yeah i am having a hard time because my teacher gave me a specific site to get buildings off of, and I have to find buildings that have Early Christian, Byzantine, and Islamic features. But I don't know because i thought that building would of worked because it had a campanile.

Christian architechure differs from the Roman and Greek styles by the provision of a basilical space, ie, a large central vein running the length of the building.

See the images here.
http://www.google.com/search?hl=en&client=firefox-a&hs=mZq&rls=org.mozilla:en-US:official&q=basilica+architecture&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&biw=1236&bih=799&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi&ei=Ne7wT8a4BonI2AX_2-S4Cg

Islamic architecture differs only from Christian in that it features no images, only geometric patterns, often on walls, floors, and ceilings, and often these are in complex mosaic tiles.

Early Christian

http://www.google.com/search?rlz=1C1GGGE_enUS379US379&aq=f&sugexp=chrome,mod=10&sourceid=chrome&ie=UTF-8&q=early+christian+architecture

Byzantine
http://www.google.com/search?hl=en&rlz=1C1GGGE_enUS379US379&q=byzantine+architecture&oq=byzantine+architecture&gs_l=serp.1.0.0i7l4j0l6.30156.31673.0.34280.9.9.0.0.0.0.247.1048.5j1j3.9.0...0.0.-3-GqHyNOr8

Islamic
http://www.google.com/search?hl=en&rlz=1C1GGGE_enUS379US379&q=islamic+architecture&oq=islamic+architecture&gs_l=serp.3..0i7l6j0j0i7j0i10j0i7.22709.23723.0.24415.7.7.0.0.0.0.237.908.3j2j2.7.0...0.0.Vr_Zf1gTQvs

AND ~~> http://en.wikipedia.org/wiki/Alhambra