Verizon’s cheapest DSL service is about $20 a month and is fast enough for the average person’s web and email use.
Cable service such as Optimum’s is much faster, but also much more expensive – last time I priced it $40 per month with cable TV, $50 a month with internet only.
For most people I recommend DSL, because you will save $200+ per year, and you don’t really need the extra speed.
If you are getting phone service from Optimum as well, it may be a different story – I never priced their combo service package.