I was living in Waidhofen/Ybbs for about 5 years. Because of many schools like a high school, the commercial academy and the technical high school you meet many young people and it is a lively city.
The city center is devided into two parts - the upper and the lower town square. Both are well restored and small shops welcome you for shopping. Young people prefer the Milchbar for meetings friends, in Café Konditorei Piaty you get the best icecream. If you are hungry after sightseeing, just visit the Schlosswirt beside the church, the Ybbsturmstube or the Hotel Restaurant Moshammer on the other side of the river.
If you like doing sports, Waidhofen/Ybbs is perfect for you. The surrounding hills offer many mountain bike and hiking tracks. You get a map for free at the tourist office or on https://www.niederoesterreich.at/mbike.
The ski area Forsteralm is about 10 kilometers away and offers 18 slopes and 8 lifts. Due to the near distance and the fair prices, you can even go up after lunch! But check if there is enough snow on their website before you start!