There's nothing particularly technical up there, it's turfy / boggy terrain with paths that are reasonably distinct but variable. But likely to be a very long slow drag as there's a lot of height to gain.
Once up you have limited options for coming back down – the descent to Hartsop is very steep, it's rideable, but not for your missus by the sound of it.
However she'd probably manage the descent from the cockpit to Howtown which is a lovely swoopy rocky/gravelly bridleway but nothing too steep or intimidating. (Will be busy with walkers, but so will everywhere…)
As ampthill said the Tour de Skiddaw from Keswick would be a decent lower-level option if you don't mind a road section up the A591 – then down past Skiddaw House hostel and under Lonscale Fell, short push up a rocky path then an airy section perched high on the fellside, round to Latrigg and down through the woods.
Or a northerly loop around the Caldbeck fells – Skiddaw House, Caldew valley (lovely remote trail though liable to be boggy) and connecting via the back roads and mining trails.
Hopefully you're aware the forecast is strong northerly winds and unseasonably cold temperatures on the hilltops.