Will be staying in Wellingborough for a weekend soon. Any good spots to hit on a Friday/Saturday night? Something a bit young and lively?
There's nothing spectacular - it's a small market town with a population that isn't big enough to support much in the way of cafe culture. Even the local nightclub closed a while ago. There are a couple of places worth a look if you don't want to do the trip to Northampton (The centre of the town there is a lot more lively, a big square surrounded by pubs and it's only a short trip. The other option of "Kettering" is much the same as Wellingborough to be frank - if you're willing to do the travel, hit Northampton).
If you do stay in Wellingborough, the town centre is the only place to bother with, and you should look for "Market Street", the (badly) pedestrianised main street with lots of cash machines and the main entrance to the shopping centre. At one end, you'll find an open area with three late night pubs, which are all busy at every weekend - the Gloucester, Cutting room and Raffarties. At the other end (and down the hill a little), there is the Horseshoe, which is open until 4ish. There are other pubs dotted around, but those four are the only ones I'd bother with given your "young/lively" criteria. (If you want somewhere nice and quiet, go find Oxford Street, a main road just outside the town centre - 5 mins walk from Market street. Look for the Coach and Horses - it closes at 11pm, but people use it as a starting point because the beer is excellent)
I would forget Wellingborough it is like a ghost town.
Your experience will depend on which day(s) you're staying and what you're looking for. I live in the town and would be happy to help if you can give a bit more detail.