1. The tank is not guaranteed to get any algae problems at all as long as you maintain proper lighting & nutrient levels in the tank. Sometimes the best way to get rid of algae is to simply get live aquarium plants to establish themselves in the tank (Flourish Excel- excellent aquarium plant fertiliser for this

!).
2. There are many different types of pleco's, some eat wood and some don't- the wood they eat is usually bogwood or driftwood which you can get from your LFS. But then bogwood leaches out tannins and can stain the aquarium water for a while. Also a lot of pleco's make pretty poor algae eaters, only concentrating on the stuff when they are young. They also poop a lot and so can actually ironically end up contributing to algae problems in the long run if there's an excess of nutrients in the tank causing the problem.
There are also different types of algae- few algae eating fish eat every type. Oto's make a much better small algae eating aquarium fish (only grow to 2inches) but they're sociable and so need to be kept in groups and they're also quite sensitive to water quality etc (so not recommended for newly set up tanks).
3. Some snails are better at eating algae than others, though i'm not totally sure which ones are the best for algae eating. Apple Snails are a large growing attractive orenmental snail which are popular additions to aquariums and will eat some algae (they also don't breed out of control). They come in golden form and natural colour form.
Personally i would just recommend going down the establishing plants route to prevent algae problems. A while back my 30gal Swordtail rearing tank got really bad Black Hair Algae and i tried almost everything to get rid of it, but to no avail. I did have live plants in the tank but even they were getting covered by the black algae and weirdly when i tested the water there was almost no nitrates in it (i expected there to be a lot as high nitrates can fuel algae problems). But then i learnt that while some algae problems can come about because of an excess of nutrients, other types of algae problems can come about because of a lack of nutrients.
The problem with my tank was that it had too little nutrients and while the plants in the aquarium were just surviving, there wasn't a large enough or consistent enough source of nutrients to get them properly established. So i started dosing the tank with large daily doses of Flourish Excel, and not only did my aquarium plants start growing again but the Black Hair Algae started to go away as the plants started to out-compete them.
In the end i didn't even have to wipe the glass once, just a few weeks of Flourish Excel treatment and all the algae in the tank was gone (and my plants looked great too!)

.
Here's a really great link on ID'ing different types of algae and how to get rid of them

v ;
http

/www.theplantedtank.co.uk/algae.htm