A two minute drive from you is Ithan Market, ithanmarket.com which does really good basic sandwiches to go (intersetction of Newtown rd and Conestoga).
A five minute drive away is Antonella's Italian Kitchen www.antonellaskitchen.com which does amazing (if a little more expensive) sandwiches/rolls, with a wider pasta/entre menu and sit in area also. Their specials are updated on the website daily and usually include a $5 special of pasta or a hoagie.
Both places serve great food with friendly staff, just depends what mood you're in.
333 Belrose is great for high quality fresh food. Go meet the bartender Mike Shea....he won best of the Main Line. They have half price appies at the bar Mon-Thurs too for happy hour.
Sometimes we do Gulifty's, Johnnie's Doghouse, Dimeo's Pizza, Vic & Dean's, John's Village Market. Mixx is new in Villanova and not bad for lunch. Some people here even go to the food court at KOP mall.
What building are you working in? The Deli at Radnor Court is great for grabbing lunch to bring back to the office. It's in the lobby of 259 Radnor Chester Road....we walk there from a couple buildings away. I'm not a fan of Duffy's.
Wayne is just a mile up the Pike with Margaret Kuo's, Teresa's, and a few new places on North Wayne Ave. Also, for great deli, Landis Catering has never wavered in its quality and is usually overlooked for a solid selection of homemade soups, salads and sandwiches. Incredible imported beer selection as well. As for Radnor, I'd skip Susanna Foo's - pricey, bland, and uninspired.
I have worked there for 2 years and I am still looking for the same thing! Best is 333 Belrose-- good but not great. Pleasant setting. Lots of places look good in the area but the food is uneven. Most of us go to Bertucci's or Tango in Bryn Mawr.
For a little hole in the wall for a unique hot dog...Try Johnnie's Dog House.