Yeah, when it comes to screens, the bigger the better I say... especially considering you mentioned portability not being a huge part of the laptop experience for yourself personally. If it's going to be set up on a desk for 90% of it's usage, then I'd go the 17" myself.
Since I port mine around a LOT, I went for the ultra tiny 10" widescreen, and for the "main" laptop which doesn't move around a huge amount, I went for the 15" since it does get ported around the house a fair bit.
~Sol