Orrrrr - go to the tech museum for the star wars exhibit:
http://www.thetech.org/plan-your-visit/special-exhibitions/STAR-WARS
This is what I was going to suggest. Other than Santa Cruz, of course.
Yeah, downtown, if you don’t have a car. #10 bus from SJC to the light rail.
Also, the Computer History Museum in Mountain View is worth a visit and just a short drive from San Jose airport.
But he’ll hit the [del]rush hour drive [/del] parking lot when he finishes there.
When I lived in that quadrant of the galaxy, I was fond of eating at Harry’s Hofbrau, located (IIRC) on the corner of Saratoga (Ave.? Blvd.?) and Kiely, which is just a block from I-280 at the Saratoga (Ave.? Blvd.?) off-ramp. It’s a cafeteria style restaurant with turkey plate or sandwich or your choice of a variety of other hot entrees, hot veggies, and salad items. The turkey is real turkey, cooked on-site and carved before your very eyes, NOT that pre-cooked pre-sliced toilet-paper-thin stuff you often find elsewhere. It can be crowded and noisy with a long line during the lunch and dinner rush hours, but rather quiet in-between times.
You might be able to navigate within a ± 1-city radius of wherever you are, but don’t push it much beyond that. Yes, traffic is bad. Or jump in your TARDIS and do Santa Cruz, San Francisco, AND Santa Barbara to your heart’s content, and be back in Silicon Gulch for your evening date.
There’s always the Winchester Mystery House on Winchester Blvd. (duh) just off I-280 and just off Stevens Creek Blvd. (if they have that big overturned truck from this morning cleared out by then :eek: – But properly seeing that might take more time than you have. I don’t know if you need to buy tickets long in advance to get in. There’s a multi-theater movie complex just across the street from that.
Weather permitting (which it won’t be, there being much rain forecast for the next few days), there are mountains just up the hill from Saratoga with parks with excellent hiking trails among the redwoods, if you’re into that kind of stuff. Another outdoorsy thing of some small interest: Up near the top of Page Mill Road in Palo Alto, there is a smallish park with a smallish little trail, where you can see a variety of visible geological artifacts of the 1906 San Francisco earthquake, like split/displaced fences, a sag pond (that may or may not have water in it), and some other stuff like that. If you’re lucky, there might be brochures there for a self-guided little tour.
Oh, did anyone mention that there are parks with hiking trails around Santa Cruz too? 
Oh, and here’s a biggie: The Computer History Museum in Mountain View. It’s just off of Hwy. 101 near the Hwy 85 junction; you can google its location easily. Worth a peek! ETA: Oops – ninjaed by Shalmanese on this one. Worth a peek!
The big mall complex he mentions (just in case your idea of entertainment is a big mall complex, of course) is just a couple block from the Winchester Mystery House, BTW.
Based on the OP’s desires, I recommend the Bean Scene in downtown Sunnyvale’s historic Murphy Ave. It’s not a chain, and is a clean well-lighted place to sit and sip and log in and work/read/surf for a little while. Use Central Expressway to get to Sunnyvale from San Jose, and then the same to get to Santa Clara. It moves well enough at that hour.
Murphy Ave was recently renovated (street and sidewalks) and they did a nice job. If you’re lucky enough to find parking on Murphy Ave (and do try), good on ya’, but there are several parking lots nearby. Parking is free.
Palo Alto’s University Ave is nice, but a tad too far given the time. And Burlingame is way too far away - you’d spend most of your 3 hours getting to/from, with about 60-90 minutes left to relax.
Mountain View’s Red Rock Coffee Shop is nice, too, but a little further than Sunnyvale.
Enjoy.
There are actually two big mall complexes near the Winchester Mystery House: Valley Fair is a big enclosed mall, fairly upscale-ish, with a nice food court (recently refurbished with some nice non-chainy spots), and Santana Row is an outdoor shopping area with more upscale shops, restaurants, and outdoor entertainment (though if it rains that might not be quite so much fun).
Interesting. I lived in the area some 25+ years ago and have only passed through briefly a few times since. Valley Fair mall (this is the one directly across Winchester Blvd. from the Winchester Mystery House) used to be a passably nice mall, but fell on hard times. Last I saw it, some years ago, it was an abandoned derelict decaying wreck of a place. If it’s the same place you mention, it must have been re-built very nearly completely (I don’t remember it being an indoor mall). The other big mall in the area was (IIRC) more-or-less across Stevens Creek Blvd. from that. Much has changed beyond recognition since I left.
Another outdoorsy place, for anyone who likes rain (given that it’s going to rain): You could actually hike around, you know, Stevens Creek. Just drive out Stevens Creek Blvd. to the far other end (Los Altos or beyond, or somewhere out there); where it ceases to be a major Blvd. and fizzles out into a petty side-street, turn left and drive up into the hills there a ways. There, find a park (I think it’s actually called Stevens Creek Park, or similar) with trails and a creek. Stevens Creek, to be specific.
Valley Fair is actually across Stevens Creek from the WMH (with a few other places in between). It’s been remodeled recently and has quite a few upscale stores along with the standard mall fare like Forever 21 and Hot Topic. I think you’re thinking of the outdoor mall that used to be where Santana Rowis (I think it was called Town and Country, but I might be misremembering). They tore that down years ago and replaced it with a series of high-end stores and restaurants with expensive loft housing above the stores. It’s quite nice now if you’re into that sort of thing.
Yes, this. That jogs my memory! It was Town & Country that I had in mind (the place that fell into ruins), not Valley Fair. Now that I think of it too, the Valley Fair mall I remember was (and maybe still is) up in Sunnyvale, somewhere in the area of Stevens Creek Blvd. and DeAnza college? (Or maybe I’m even mis-remembering the name of that mall.)
As Chief Bromden wrote in the final line of Cuckoo’s Nest: I been away a long time.
I love Harry’s Hofbrau! It’s confusing though because you walk in and think huh, this place is weird, but then they feed you and it’s so good!
Nope, Valley Fair is in Santa Clara on Stevens Creek, and the area near Stevens Creek and De Anza would be Cupertino. There used to be one in Sunnyvale called the Town Center (actually there were two, one across the street from each other–the Town and Country was an outdoor mall like the one mentioned above (same company), and the Sunnyvale Town Center was an enclosed mall. Neither one of them was nearly as nice or upscale as Valley Fair. The Town and Country is gone now, I’m pretty sure the Town Center is too (or else they’ve completely redone it–I know there’s a Target there, but not sure about anything else from the old one).
The Town Center was the first mall I ever went to after we moved to the Bay Area in 1989–we lived in Sunnyvale, a couple of miles away.
Okay, I did the unthinkable and looked on Google Maps. I guess I’m thinking of Vallco, which appears to be a big mall on N. Wolfe Rd. near Stevens Creek. I recall it being a big mall that was on both sides of the road, with some part of the upper level of the mall actually passing over the road. I think that was the food court area. Am I getting any better?
I know! Our OP can drive up Mt. Hamilton and visit Lick Observatory up at the top! Then he can drive down the other side of Mt. Hamilton and visit the wineries in Livermore area. Then he could take a brief swing through Santa Cruz on the way back to Santa Clara from there! 
Yep! Vallco is still there. It used to be a really nice mall back in the day, but it kinda fell on hard times. For a while it was quite the dump, but they’re slowly refurbishing it and it’s getting a little nicer again. At least it has a nice new cinema complex now, though the lower level is almost all deserted and the upper level is mostly one-off local shops. We still go there because it has one of the best game/comic/geek memorabilia stores in the area (Legends).
I hope he has a flying car! Especially since with the rain today, the roads are going to all be nightmares since everybody in California forgets how to drive when the water falls from the sky. 
I’m a little surprised no one has suggested places in Santa Fe!
Thanks for the suggestions, guys! I’m leaning toward heading into downtown San Jose and hanging out there. And thanks for warning me about traffic.
Listen to some Dionne Warwick.
You’ll be sure to come back to this thread tomorrow and tell us what you did, yeah? We’ll be wanting to know if you ever make it to Santa Cruz!