Yea.. the vidal sassoon school is right along 3rd street in Santa Monica.
Too bad you guys aren't coming this weekend; the MAC store on 3rd street is having an event. But it'll still be fun just going there with you guys. Then 2 or 3 shops down the street there's a Sephora. About 3 shops down from Sephora there's a Fresh store, and across from Fresh there's a LUSH store.
It's close to where I live and work (I went to UCLA and have settled near by), and it's just amazing here.
As for your hotel.. yes, it looks close. It IS close mile-wise. But in traffic, it could take up to an hour for you to get to the airport. (Grew up near Del Amo Mall, and the 405 freeway and I are bosom buddies) =D Try to get a rental car with a navigation system because that would help so much.
And I actually hate Del Amo Mall. There's not too much great stores, and there's tons of high school kids running around. I really really hate going there, even though it's so close to my parents' house. Heck, my middle school is across the street from Del Amo Mall (oooh that may explain the kid part).
Century Mall in Century City (about 5 miles from Santa Monica) is much better IMO. It's got the nice huge movie theater, a GREAT dining area (bars, restaurants, and outdoor seating), PINKBERRY (if you haven't tried Pinkberry, you are in for a treat), Sephora, LV, Coach, L'occitane, Bloomingdales, Macy's, and so much more great stores. There's even a ProActiv vending machine at Century Mall. =D
What else is there in LA that you must see. OOoh, the Max Factor Museum. It's in West Hollywood across the street from the Kodak Theater, right by a Ripley's Believe it or Not museum. You guys have to go there.
You can also see what premieres are happening the weekend your here. I use to catch them by surprise and would it's just so fun to stand by the red carpet, screaming "CAMERON, CAMERON, LOOK THIS WAY!!!" or "OMIGOD IT'S BIG TIME A-LIST STAR".. and since they are on the red carpet, they're in a better mood than you attacking them on a random street, and more likely to smile or wave to you. =D