Will PoS lead to a run on other resources like hard drives?
It could potentially lead to a run on Ethereum. The resource used in PoS is the cryptocurrency being secured itself. Basically, you agree to lock up a certain stake when you run a validator, and forfeit it if it's found that your validator "cheats". By doing this, you make cheating unprofitable - there's a financial incentive to catch cheats, and a financial disincentive to cheat, and the cheaters eventually go bankrupt (or end up on their own isolated chain where nobody transacts with them).
The financial effect of this is that a bunch of Ethereum gets locked up and illiquid. Instead of miners receiving Ethereum which they want to sell for dollars to run their hardware, stakers lock up Ethereum and effectively receive interest. This reduces immediate supply within the market. I'm wondering if a lot of the recent price movement is in anticipation of this.
Also does eth supply increase forever or does it have a hard coin limit like btc?
For most of its history Ethereum was inflationary. It flipped and became deflationary a couple months back, and not coincidentally the price started rising again. It's likely to be significantly deflationary under Eth 2.0 with expected transaction and staking volumes.
Currently no hard cap on issuance, 2 ETH are minted every block, but ETH burn rate is expected to outpace issuance post-POS.
It's intentionally designed to be memory-hard so that ASIC implementation is more difficult. Lots of people in the cryptocurrency world consider ASIC mining to be a misfeature, because it centralizes mining among firms that have the capital to do chip development. Litecoin's entire reason for existence is "Bitcoin, but can't be mined by ASICs".
"Also when they switch to pos how do they transfer your coins over?"
There's already a beacon chain running Ethereum proof-of-stake. Think of this like a dark launch for web tech - basically you run the new infrastructure in parallel with the old infrastructure, make sure it's stable, get everybody adopting it, and then cut over the UI to use the new infrastructure.
There's a one-way bridge that ports state over from the PoW chain to the beacon chain. Think of this as a double-write layer; all new transactions get written both to the PoW and PoS chains.
In early 2022 "The Merge" happens. This takes the form of the "difficulty bomb" - basically, Ethereum mining will get exponentially harder and eventually unprofitable until all the existing miners turn off their machines and switch to PoS, at which point there will be no point to mining Ethereum and no point to writing transactions to the PoW chain.