Your screen should still be fine, though at around 100 diagonal (assuming 16:9) it's somewhat small by today's standards.
If your room is dark and you can afford it, I really like the JVC DILA offerings for their high native contrast ratios. If you room is only semi-dark or you want to watch anything with the lights on I'd go DLP for the additional light output.
For your receiver, what features matter to you? What is your speaker setup? 5.1? 7.1? 8 Ohm speakers? Any thoughts of going Atmos in the future? Any way you look at it, I wouldn't spend a fortune on a receiver as you can get a good performer for not a ton of cash. I mentioned the Onkyo Rz830 previously as I think it's a great value as it can be found for deep discounts (I bought mine new for $500). If you haven't been in the market for 15 years you might not know the current state of things. Onkyo/Integra has bought Pioneer, so now Onkyo/Integra/Pioneer/Pioneer Elite all share a lot of the same architecture and parts. Denon has merged with Marantz so internally Denon and Marantz receivers have virtually the same architecture and parts. Yamaha is still separate.
Onkyo/Pioneer is known to have the most features for the price but is known to run hot and have had HDMI board issues in the past (they extended their warranty for the HDMI board a few years back) They claim the HDMI board issues are fixed, but we may not know that for a year or two. Onkyo offers their own calibration program "AccuEQ" that replaced Audyssy in their units a few years ago. I have run into some people that prefer "AccuEQ" but the general consensus is "Audyssy" is the better calibration program.
Yamaha is thought of by most to be the most reliable, but they don't offer many features for the price. This might not be a huge deal for you as you probably aren't looking for a ton of features. Yamaha offers their own calibration program YPAO (which I've never used so I don't know much about)
Denon/Marantz are probably the middle of the road for features vs price. They do use Audyssey MultEQ calibration software that most people feel is the best of the mojor brand reciever calibration systems (NAD uses DIRAC which is supposed to be the best, but they are more niche)
7.4.4 Theater Room: JVC-RS500, Silver Ticket AT 2.35:1 142”, Onkyo RZ830, Anthem PVA-7, Panasonic DBT-110, JBL Studio 530’s, 4 - 15" DIY Sealed Subs
3.1 Living Room: Samsung 64” F8500 Plasma, Anthem MRX 300, Dynaudio Audience 52’s, Dynaudio Audience 122C, NHT SubOne